Free online calculators for everything
Over 311 fast, accurate tools across 19 categories. Fast results. No signup. Everything runs privately in your browser.
Popular calculators View all (311)
Loan Payment Calculator
Monthly payment, total cost, and interest.
Compound Interest Calculator
See how savings grow with monthly compounding.
BMI Calculator
Body mass index from weight and height.
Percentage Calculator
Find X percent of any number.
Temperature Converter
Celsius, Fahrenheit, and Kelvin at once.
Tip Calculator
Split the bill and tip between friends.
Mortgage Calculator
Monthly mortgage payment from price, down payment, and rate.
Calorie Calculator
Daily calories to maintain, lose, or gain weight.
Heart Rate Zones Calculator
Training heart rate zones using the Karvonen method.
Fuel Economy Calculator
Fuel consumption in L/100 km, km/L, and miles per gallon.
GPA Calculator
Weighted GPA from grade points and credits.
Markup Calculator
Selling price, profit, and margin from cost and markup.
Ohm's Law Calculator
Current and power from voltage and resistance.
Recipe Scaler
Scale an ingredient amount up or down for more or fewer servings.
Car Loan Calculator
Monthly car payment, interest, and total cost.
Running Pace Calculator
Pace per kilometer and speed from distance and time.
Split Bill Calculator
Divide a bill and tip evenly between people.
Download Time Calculator
How long a file takes to download at a given internet speed.
Number Base Converter
Convert a decimal number to binary, octal, and hexadecimal.
Trip Budget Calculator
Total trip cost from lodging, food, transport, activities, and flights.
Currency Converter (Manual Rate)
Convert money with your own exchange rate and fee.
Battery Runtime Calculator
How long a battery can power a load.
LED Bulb Savings Calculator
Savings from replacing old bulbs with LEDs.
Voltage Drop Calculator
Voltage drop and power loss along a cable.
Air Conditioner BTU Calculator
Cooling capacity needed for a room.
Raised Bed Soil Calculator
Soil volume and number of bags needed to fill a raised bed.
Finance Calculators
Plan mortgages, forecast compound growth, calculate tax liabilities, and optimize your monthly budget with fast, accurate financial models.
Loan Payment Calculator
Monthly payment, total cost, and interest.
Compound Interest Calculator
See how savings grow with monthly compounding.
Simple Interest Calculator
Interest earned without compounding.
Discount Calculator
Find the sale price and how much you save.
Sales Tax Calculator
Tax amount and total price at checkout.
ROI Calculator
Return on investment as a percentage.
Profit Margin Calculator
Margin, markup, and profit from revenue and cost.
Mortgage Calculator
Monthly mortgage payment from price, down payment, and rate.
Savings Goal Calculator
How much to save each month to reach a goal.
Inflation Calculator
What prices or savings will be worth after years of inflation.
VAT Calculator
Add or remove VAT from a price.
Hourly to Salary Calculator
Turn an hourly wage into daily, weekly, monthly, and yearly pay.
Break-Even Calculator
Units and revenue needed to cover your costs.
Credit Card Payoff Calculator
How long it takes to pay off a balance.
CAGR Calculator
Compound annual growth rate between two values.
Rule of 72 Calculator
Estimate how many years it takes money to double.
Retirement Savings Calculator
Projected savings at retirement with monthly deposits.
Dividend Yield Calculator
Dividend yield and yearly dividend income from a stock.
Stock Profit Calculator
Net profit, return, and break-even price after trading fees.
Debt-to-Income Ratio Calculator
See what share of your income goes to debt each month.
APR to APY Calculator
Convert a nominal APR into the effective annual yield.
Net Present Value (NPV) Calculator
Discount future cash flows to see if an investment is worth it.
Emergency Fund Calculator
Find how much cash cushion you need and how long it takes to build.
Net Worth Calculator
Add up assets and debts to see your net worth.
Extra Loan Payment Calculator
See how much interest and time extra monthly payments save.
Rent Affordability Calculator
Estimate how much rent fits your income.
Future Value of Regular Savings Calculator
See what regular deposits grow to with compound interest.
Present Value Calculator
Find what a future sum is worth in today's money.
Loan Affordability Calculator
Work out the largest loan a monthly payment can support.
Average Cost Basis Calculator
Average your purchase price across several buys and see profit or loss.
Overtime Pay Calculator
Calculate total pay including overtime hours and multiplier.
Health Calculators
Track BMI, basal metabolic rate, daily hydration targets, and vital health screening indicators right from your browser with zero data shared.
BMI Calculator
Body mass index from weight and height.
BMR Calculator
Calories your body burns at rest.
Water Intake Calculator
Daily water target based on weight and exercise.
Ideal Weight Calculator
A healthy weight estimate from height.
Calorie Calculator
Daily calories to maintain, lose, or gain weight.
Body Fat Calculator
Body fat percentage using the U.S. Navy method.
Pregnancy Due Date Calculator
Estimated due date from the first day of your last period.
Macro Calculator
Grams of protein, carbs, and fat from calories and split.
Waist-to-Hip Ratio Calculator
Body fat distribution from waist and hip size.
Lean Body Mass Calculator
Estimate lean mass and fat mass with the Boer formula.
Sleep Cycle Calculator
Bedtimes that match 90-minute sleep cycles for your wake-up time.
Body Surface Area Calculator
Estimate BSA with the Mosteller, DuBois, and Haycock formulas.
Waist-to-Height Ratio Calculator
Check central body fat with a simple waist-to-height ratio.
Weight Loss Timeline Calculator
Estimate how long it takes to reach your goal weight.
Mean Arterial Pressure Calculator
Calculate MAP and pulse pressure from blood pressure readings.
Ovulation & Fertile Window Calculator
Estimate your ovulation day and fertile window from your cycle.
Ponderal Index Calculator
Body proportion index based on weight divided by height cubed.
Creatinine Clearance Calculator
Estimate kidney function using the Cockcroft-Gault formula.
Math Calculators
Solve percentages, proportions, circle geometry, statistics, and algebraic formulas with instant formulas and step-by-step clarity.
Percentage Calculator
Find X percent of any number.
Percentage Change Calculator
Increase or decrease between two values.
Average Calculator
Mean, median, and sum of a list of numbers.
Pythagorean Theorem Calculator
Hypotenuse and area of a right triangle.
Circle Calculator
Area, circumference, and diameter from the radius.
Rectangle Calculator
Area, perimeter, and diagonal of a rectangle.
Quadratic Equation Solver
Real roots of ax² + bx + c = 0.
GCD and LCM Calculator
Greatest common divisor and least common multiple.
Standard Deviation Calculator
Mean, variance, and standard deviation of a data set.
Ratio and Proportion Calculator
Solve a : b = c : x.
Triangle Area Calculator
Area and perimeter from three side lengths.
Combinations and Permutations Calculator
Count ways to choose or arrange items.
Median, Mode and Range Calculator
Median, mode, range, and sum of a list of numbers.
Sphere Calculator
Volume and surface area from the radius.
Percentage Difference Calculator
Percent difference between two values, regardless of order.
Prime Number Checker
Check if a number is prime and find the next prime.
Arithmetic Sequence Calculator
Nth term and sum of an arithmetic sequence.
Factorial Calculator
Calculate n! with digit count and trailing zeros.
Permutations and Combinations Calculator
Count arrangements and selections of r items from n.
Slope and Distance Calculator
Distance, slope, midpoint, and line equation from two points.
Ratio Simplifier
Reduce a ratio of two whole numbers to its simplest form.
Logarithm Calculator
Log of any number in any base, plus ln, log10, and log2.
Fraction Calculator
Add, subtract, multiply, or divide two fractions.
Z-Score Calculator
Find how many standard deviations a value is from the mean.
Nth Root Calculator
Find square roots, cube roots, and any other root.
Cylinder & Cone Calculator
Volume and surface area for a cylinder and a cone of the same size.
Conversion Calculators
Switch seamlessly between metric and imperial systems for temperature, length, volume, speed, digital data storage, and weights.
Temperature Converter
Celsius, Fahrenheit, and Kelvin at once.
Length Converter
Meters, kilometers, miles, feet, and more.
Weight Converter
Kilograms, grams, pounds, and ounces.
Speed Converter
Convert km/h, m/s, mph, and knots.
Volume Converter
Liters, milliliters, gallons, cups, and fluid ounces (US).
Area Converter
Square meters, square feet, acres, and hectares.
Data Storage Converter
Bytes, KB, MB, GB, and TB (decimal units).
Time Converter
Convert seconds, minutes, hours, days, weeks, and years.
Pressure Converter
Convert Pa, kPa, bar, psi, atm, and mmHg.
Energy Converter
Convert joules, calories, watt-hours, and kilowatt-hours.
Angle Converter
Convert degrees, radians, gradians, and turns.
Area Converter
Convert between square meters, acres, hectares, square feet, and more.
Volume Converter
Convert liters, gallons, cups, ounces, cubic feet, and more.
Speed Converter
Convert km/h, mph, m/s, knots, feet per second, and Mach.
Power Converter
Convert watts, kilowatts, horsepower, and BTU per hour.
Force Converter
Convert newtons, pound-force, kilogram-force, and more.
Torque Converter
Convert newton-metres, pound-feet, pound-inches, and kgf-m.
Frequency Converter
Convert hertz, kilohertz, megahertz, gigahertz, and RPM.
Everyday Calculators
Handy tools for daily decisions—calculate exact ages, split restaurant bills, count down important dates, and estimate tips effortlessly.
Age Calculator
Your exact age in years, months, and days.
Tip Calculator
Split the bill and tip between friends.
Days Between Dates Calculator
Count the days between two dates.
Date Calculator
Add or subtract days from a date.
Time Duration Calculator
Hours and minutes between two times.
Fuel Cost Calculator
Fuel needed and cost for a trip.
Unit Price Calculator
Compare two products by price per unit.
Countdown Calculator
Days remaining until a date.
Electricity Cost Calculator
What a device costs to run.
Split Bill Calculator
Divide a bill and tip evenly between people.
Working Days Calculator
Count weekdays between two dates, both included.
Roman Numeral Converter
Turn a number from 1 to 3999 into Roman numerals.
Birthday Countdown Calculator
Days left until your next birthday and the age you will turn.
Pizza Size Value Calculator
Which pizza gives you more for your money?
Leap Year Checker
Check if a year is a leap year and find the next one.
Day of the Week Calculator
Find the weekday, day of year, and week number for any date.
Dog Age Calculator
Convert dog years to human years by size.
Word Counter
Count words, characters, sentences, and reading time.
Year Progress Calculator
See how much of the year has passed and how much is left.
Carpool Savings Calculator
Compare commute costs per person when you share the ride.
Subscription Cost Calculator
Add up what your monthly and yearly subscriptions really cost.
Education Calculators
Calculate cumulative GPA, weighted course grades, required final exam scores, and weekly study schedules to stay ahead in school.
GPA Calculator
Weighted GPA from grade points and credits.
Final Grade Calculator
The score you need on the final exam.
Test Score Percentage Calculator
Percentage and letter grade from points.
Reading Time Calculator
Estimated reading and speaking time.
Weighted Grade Calculator
Overall grade from scores and their weights.
Typing Speed Calculator
Words per minute and accuracy from a typing test.
Study Time Planner
Daily study hours needed to finish your material before an exam.
Attendance Percentage Calculator
Track attendance and how many classes you can still miss.
Exam Time Planner
Work out how many minutes you can spend per question.
Course Study Load Calculator
Estimate weekly study hours from your credit load.
Construction Calculators
Estimate concrete yardage, paint coverage, tile quantities, drywall sheets, and lumber requirements for DIY projects and job sites.
Paint Calculator
Paint needed to cover the walls of a room.
Concrete Calculator
Concrete volume for a slab.
Tile Calculator
Number of square tiles for a floor.
Flooring Calculator
Flooring area and boxes needed, including waste.
Gravel and Mulch Calculator
Volume and weight of gravel for an area.
Brick Calculator
Number of bricks for a wall, including mortar joints and waste.
Stair Calculator
Number of steps, exact riser height, and total run for a staircase.
Drywall Calculator
Estimate drywall sheets and joint compound for a room.
Roof Area and Shingles Calculator
Estimate roof surface area, squares, and shingle bundles from pitch.
Wallpaper Calculator
Find how many rolls of wallpaper you need.
Fence Materials Calculator
Count posts, rails, and pickets for a fence run.
Mulch & Soil Volume Calculator
Cubic yards and bags needed to cover a garden bed.
Business Calculators
Calculate gross margin, pricing markups, sales commissions, break-even thresholds, and payback periods to scale your business.
Markup Calculator
Selling price, profit, and margin from cost and markup.
Commission Calculator
Commission earned and total pay from sales.
Invoice Total Calculator
Invoice total with discount, tax, and shipping.
Payback Period Calculator
How long an investment takes to earn its money back.
Customer Lifetime Value Calculator
Estimate how much a customer is worth over the full relationship.
ROAS Calculator
Return on ad spend, profit after ads, and break-even ROAS.
Customer Acquisition Cost Calculator
Find your CAC and compare it with customer lifetime value.
Churn Rate Calculator
Measure customer churn, retention, and expected lifetime.
Inventory Turnover Calculator
See how many times you sell through stock each year.
Economic Order Quantity Calculator
Find the order size that minimizes ordering and holding costs.
Employee Turnover Rate Calculator
Measure how many staff leave relative to your average headcount.
Ecommerce Conversion Rate Calculator
Turn visits and orders into conversion rate and revenue metrics.
Science Calculators
Solve fundamental physics laws, kinetic energy, velocity, gas laws, and molar mass equations with complete formula breakdowns.
Ohm's Law Calculator
Current and power from voltage and resistance.
Kinetic Energy Calculator
Energy and momentum of a moving object.
Density Calculator
Density from mass and volume.
Free Fall Calculator
Fall time and impact speed from a given height.
Half-Life Calculator
Amount of a substance left after a given time.
Wavelength and Frequency Calculator
Convert a wave frequency to wavelength using the speed of light.
Molarity Calculator
Solution concentration from mass, molar mass, and volume.
Projectile Motion Calculator
Range, peak height, and flight time of a launched object.
Ideal Gas Law Calculator
Solve PV = nRT for pressure, volume, temperature, or moles.
pH Calculator
Convert between pH, pOH, H+ and OH- concentration.
Specific Heat Calculator
Heat needed to warm or cool a material: Q = m × c × ΔT.
Newton's Second Law (F = ma) Calculator
Force from mass and acceleration, with speed and distance after a time.
Dilution Calculator (C1V1 = C2V2)
Find how much stock solution you need for a target concentration.
Cooking Calculators
Resize recipes for any serving count, convert cups to grams, estimate roast cooking times, and bake with exact culinary proportions.
Recipe Scaler
Scale an ingredient amount up or down for more or fewer servings.
Cooking Measurement Converter
Convert cups, spoons, milliliters, and fluid ounces.
Coffee Ratio Calculator
Coffee grounds needed for the water you brew with.
Oven Temperature Converter
Celsius to Fahrenheit, gas mark, and fan oven setting.
Rice to Water Ratio Calculator
How much water to cook your rice.
Meat Per Person Calculator
How much meat to buy for a meal or party.
Bread Hydration Calculator
Total hydration, salt, and starter percentages for sourdough.
Pizza Dough Calculator
Flour, water, salt, and yeast for any number of pizzas.
Recipe Nutrition per Serving Calculator
Calories and macros per serving from the recipe totals.
Automotive Calculators
Evaluate true vehicle ownership costs—auto loan monthly payments, fuel economy MPG, vehicle depreciation, and EV charge speeds.
Fuel Economy Calculator
Fuel consumption in L/100 km, km/L, and miles per gallon.
Car Loan Calculator
Monthly car payment, interest, and total cost.
Car Depreciation Calculator
Estimated car value after several years.
EV Charging Cost Calculator
Cost to charge an electric car between two battery levels.
Tire Size Calculator
Overall diameter, sidewall height, and circumference from a tire code.
Car Lease Calculator
Monthly lease payment from price, residual value, term, and rate.
Engine Displacement Calculator
Engine size in cc, liters, and cubic inches from bore and stroke.
Cost per Mile / km Calculator
Total ownership cost of a vehicle per distance unit driven.
Car Ownership Cost Calculator
Yearly and monthly cost of running a car, fuel included.
Fitness Calculators
Calculate running splits, one-rep maximums, target heart rate zones, and daily protein targets to reach your fitness goals faster.
Heart Rate Zones Calculator
Training heart rate zones using the Karvonen method.
Running Pace Calculator
Pace per kilometer and speed from distance and time.
One-Rep Max Calculator
Estimate your maximum single lift from a multi-rep set.
Calories Burned Calculator
Calories burned by common activities.
Protein Intake Calculator
Daily protein target for your activity level.
Steps to Distance Calculator
Convert steps to kilometers, miles, time, and calories.
Race Time Predictor
Predict 5K, 10K, half marathon, and marathon times from one result.
VO2 Max Calculator (Cooper Test)
Estimate aerobic fitness from a 12 minute run.
Body Fat Calculator (Navy Method)
Estimate body fat percentage from tape measurements.
Technology Calculators
Convert binary and hexadecimal numbers, verify display aspect ratios, test password entropy, and estimate file download speeds.
Download Time Calculator
How long a file takes to download at a given internet speed.
Number Base Converter
Convert a decimal number to binary, octal, and hexadecimal.
Aspect Ratio Calculator
Simplest aspect ratio and the matching height for a new width.
Password Strength Calculator
Estimate password entropy from its length and character set.
PX to REM Converter
Convert pixels to rem, em, points, and percent for CSS.
Video File Size Calculator
Estimate file size from bitrate and duration.
CIDR / Subnet Host Calculator
Subnet mask and usable host count for a CIDR prefix.
RAID Capacity Calculator
Usable storage and fault tolerance for common RAID levels.
Travel Calculators
Plan vacations with confidence—estimate road trip fuel costs, calculate daily travel allowances, time zone offsets, and flight durations.
Trip Budget Calculator
Total trip cost from lodging, food, transport, activities, and flights.
Currency Converter (Manual Rate)
Convert money with your own exchange rate and fee.
Road Trip Planner
Driving time with rest stops, plus fuel cost for the trip.
Jet Lag Recovery Calculator
Estimate how many days your body needs to adjust to a new time zone.
Flight Time Calculator
Estimate flight duration from distance and cruising speed.
Energy Calculators
Calculate solar panel array output, battery backup runtime, appliance power bills, wire gauge sizes, and electrical load safely.
Solar System Size Calculator
Estimate the solar array size and number of panels your home needs.
Solar Panel Output Calculator
Daily, monthly, and yearly energy from a set of solar panels.
Solar Payback Period Calculator
How many years a solar system takes to pay for itself.
Solar Charge Controller Size Calculator
Pick the right charge controller current for your panels and battery bank.
Battery Runtime Calculator
How long a battery can power a load.
Battery Bank Size Calculator
Size a battery bank for off-grid or backup power.
Battery Charge Time Calculator
Estimate how long a battery takes to charge.
Power Bank Charges Calculator
How many times a power bank can charge your phone.
LED Bulb Savings Calculator
Savings from replacing old bulbs with LEDs.
Standby Power Cost Calculator
What devices cost you while idle or on standby.
Appliance Upgrade Savings Calculator
Will a more efficient appliance pay for itself?
Daily Energy Load Calculator
Add up the daily energy use of several appliances.
Electrical Power Calculator
Real, apparent, and reactive power from volts and amps.
Three-Phase Power Calculator
Power in kW and kVA for a three-phase supply.
kVA to kW Calculator
Convert kVA to kW and current for single or three-phase supplies.
Power Factor Correction Calculator
Capacitor size needed to improve power factor.
Voltage Drop Calculator
Voltage drop and power loss along a cable.
Wire Size Calculator
Minimum cable cross-section for an allowed voltage drop.
Generator Size Calculator
Choose a generator size from running and starting loads.
Series and Parallel Resistor Calculator
Total resistance of resistors in series and in parallel.
LED Resistor Calculator
Series resistor value for an LED.
Capacitor Energy Calculator
Energy and charge stored in a capacitor.
Transformer Turns Ratio Calculator
Secondary voltage and currents from a transformer turns ratio.
Pump Power Calculator
Hydraulic and shaft power needed to pump water.
Wind Turbine Power Calculator
Estimate power from a wind turbine.
Building Heat Loss Calculator
Heat loss through walls, windows, or a roof, and the heating cost.
Air Conditioner BTU Calculator
Cooling capacity needed for a room.
Air Conditioner Running Cost Calculator
Monthly electricity cost of running an air conditioner.
Water Heater Cost Calculator
Energy and cost to heat your daily hot water.
Electricity Carbon Footprint Calculator
CO₂ emissions from your electricity use.
Gardening Calculators
Estimate soil and mulch cubic yards, calculate planting distances, seed quantities, and optimize watering schedules for vibrant gardens.
Raised Bed Soil Calculator
Soil volume and number of bags needed to fill a raised bed.
Plant Spacing Calculator
How many plants fit in a bed at a given spacing.
Lawn Seed Calculator
How much grass seed you need for a new or overseeded lawn.
Fertilizer Application Calculator
How much fertilizer to spread to hit a nitrogen target.
Garden Watering Calculator
Weekly water volume for a garden bed or lawn.
Rainwater Harvesting Calculator
Water you can collect from a roof and the barrels to store it.
Seed Starting Calculator
How many seeds to sow to end up with the plants you want.
Vegetable Garden Size Calculator
How big a vegetable garden you need to feed your household.
Pot Soil Volume Calculator
Potting mix needed to fill round planters and containers.
Growing Degree Days Calculator
Heat accumulation used to time planting and harvest.
Photography Calculators
Calculate hyperfocal distance, depth of field blur, sensor crop factors, video bitrate storage, and photography project pricing.
Exposure Value (EV) Calculator
Convert aperture, shutter speed, and ISO into an exposure value.
Depth of Field Calculator
Near and far limits of acceptable sharpness for any lens setup.
Hyperfocal Distance Calculator
Find the focus distance that keeps everything to infinity sharp.
Crop Factor Calculator
Crop factor and full-frame equivalent focal length and aperture.
Field of View Calculator
Horizontal, vertical, and diagonal angle of view for a lens and sensor.
Reciprocal Rule Shutter Speed Calculator
Slowest shutter speed you can hand-hold without blur.
ND Filter Exposure Calculator
New exposure time after adding a neutral density filter.
Exposure Stops Difference Calculator
Compare two exposure settings and see the difference in stops.
Equivalent Exposure Calculator
New shutter speed that keeps exposure the same after changing aperture or ISO.
Print Size from Pixels Calculator
Largest print you can make from an image at a chosen quality.
Resolution Needed for Print Calculator
Pixels and megapixels required for a print of a given size.
Pixel Pitch and Diffraction Calculator
Pixel size and the aperture where diffraction starts to soften images.
Photo Storage Calculator
How many photos fit on a memory card and how long it lasts.
Video Recording Time Calculator
How many hours of video fit on a card at a given bitrate.
Slow Motion Calculator
Slow-down factor and final clip length from frame rates.
Shutter Angle Calculator
Convert between shutter angle, frame rate, and shutter speed.
Time-Lapse Calculator
Frames, clip length, and storage for a time-lapse sequence.
Flash Guide Number Calculator
Aperture needed for correct flash exposure at a given distance.
Light Falloff Calculator
How much light you lose when you move a light farther away.
Macro Magnification Calculator
Reproduction ratio, effective aperture, and exposure loss for close-ups.
Shooting Distance Calculator
How far to stand to fit your subject in the frame.
Drone Ground Sampling Distance Calculator
Ground resolution and image footprint for drone mapping.
Panorama Shots Calculator
Number of photos for a full 360° panorama with overlap.
Astrophotography NPF Rule Calculator
Longest exposure before stars turn into trails.
Sunny 16 Rule Calculator
Estimate exposure outdoors without a light meter.
Print Viewing Distance Calculator
Best viewing distance for a print and the resolution it really needs.
Crop Zoom Resolution Calculator
Resolution left after cropping in to simulate a longer lens.
Film Reciprocity Failure Calculator
Corrected exposure time for long film exposures.
Film Cost per Frame Calculator
True cost of shooting film including development and scanning.
Photographer Hourly Rate Calculator
Hourly rate you need to charge to reach your income goal.
Pets Calculators
Calculate daily feeding calories for dogs and cats, aquarium volume and filter turnover, horse hay requirements, and lifetime pet care costs.
Dog Daily Calorie Calculator
Daily calories and cups of food for a dog by weight and life stage.
Cat Daily Calorie Calculator
Daily calories and cups of food for a cat by weight and life stage.
Pet Food Cost Calculator
Daily, monthly, and yearly food cost plus how long a bag lasts.
Pet Weight Loss Timeline Calculator
How many weeks a pet needs to reach its target weight at a safe weekly pace.
Puppy Adult Weight Calculator
Estimate how much a puppy will weigh when fully grown.
Cat Age in Human Years Calculator
Convert your cat's age to human years and see its life stage.
Pet Daily Water Intake Calculator
How much water a dog or cat needs each day by weight.
Aquarium Volume Calculator
Water volume of a rectangular tank in liters and gallons.
Aquarium Stocking Calculator
Rough number of small fish a tank can hold using the inch-per-gallon rule.
Aquarium Water Change Calculator
How much water to replace to bring nitrate down to your target.
Aquarium Heater Size Calculator
Heater wattage needed to warm a tank from room temperature.
Aquarium Treatment Dose Calculator
Scale a water conditioner or medication dose to your tank volume.
Aquarium Filter Flow Rate Calculator
Pump or filter flow you need for the tank size and turnover you want.
Aquarium Weight Calculator
Total loaded weight of a tank and the load it puts on the floor.
Pet Monthly Cost Calculator
Monthly, yearly, and lifetime cost of owning a pet.
Pet Insurance Break-Even Calculator
Compare your yearly cost with and without pet insurance.
Pet Treat Allowance Calculator
How many treats fit in your pet's daily calorie budget.
Dog Crate Size Calculator
Minimum crate length and height for your dog.
Pet Boarding Cost Calculator
Total cost of boarding one or more pets, with a multi-pet discount.
Horse Hay Needs Calculator
Daily, monthly, and yearly hay for one or more horses.
Real Estate Calculators
Analyze investment properties with capitalization rates, gross and net rental yield, closing costs, down payments, and seller proceeds.
Rental Yield Calculator
Gross and net rental yield from price, rent, and expenses.
Cap Rate Calculator
Capitalization rate and implied value of an income property.
Cash-on-Cash Return Calculator
Yearly cash flow as a percentage of the cash you put into a rental.
Rental Property Cash Flow Calculator
Monthly and yearly cash flow after every cost of a rental.
Gross Rent Multiplier Calculator
GRM of a rental and its value at the market multiplier.
Rent-to-Price Ratio Calculator (1% Rule)
Check a rental against the 1% and 2% rules of thumb.
DSCR Calculator (Debt Service Coverage Ratio)
Debt service coverage ratio and the largest loan your income supports.
Down Payment Calculator
Down payment, closing costs, and total cash needed to buy a home.
Closing Costs Calculator
Estimate buyer closing costs from the loan and the price.
Property Tax Calculator
Annual and monthly property tax from value, rate, and exemptions.
Home Appreciation Calculator
Future home value and gain at a steady yearly growth rate.
Home Equity and LTV Calculator
Equity, loan-to-value ratio, and how much you could borrow against it.
Price per Square Meter / Foot Calculator
Price per square meter and square foot, compared with the market.
House Flip Profit Calculator
Profit, ROI, and the 70% rule maximum offer for a flip.
Home Sale Net Proceeds Calculator
Cash you walk away with after commission, closing costs, and your mortgage.
Real Estate Commission Calculator
Total commission, the buyer and listing sides, and an agent payout after the split.
Mortgage Points Break-Even Calculator
Whether buying discount points pays off before you sell or refinance.
Refinance Break-Even Calculator
Monthly savings and months to recover refinance costs.
Prorated Rent Calculator
Rent due for a partial month from a move-in date.
Floor Area Ratio (FAR) Calculator
FAR, building coverage, and remaining buildable area under zoning limits.
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toolsfree.biz.id is a comprehensive collection of free online calculators designed to give you quick, reliable answers for finance, health, math, unit conversions, construction, and everyday decisions.
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Do my numbers or calculation values leave my device?
No. All calculations run strictly inside your browser using client-side JavaScript. Nothing you type is transmitted to or stored on our servers.
Can I use the calculators for commercial or business purposes?
Yes, you may use the results for personal, educational, and commercial purposes in accordance with our terms of use.
Are the calculator results exact?
Calculations are computed with precision and rounded for clean display. For high-stakes financial, medical, or legal decisions, always verify with a certified professional.
How do I request a new calculator or report a bug?
We welcome feedback! Please send us a message through our Contact page with details about the tool you need or the issue you found.
Disclaimer & Usage Information
The calculators provided on toolsfree.biz.id are for general educational, personal, and informational purposes only. Screening tools (such as BMI) are not medical diagnoses, and financial estimations are not formal tax or investment advice. Please review our Disclaimer, Terms of Use, and Privacy Policy.