Every answer starts with a good calculation.

Home

AC BTU Calculator

Size air conditioning BTU needs from room size and sun exposure.

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Science

Acceleration Calculator

Calculate acceleration from change in velocity over time.

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Finance

Affordability Calculator

Estimate home affordability from income, debts, and down payment.

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Date & Time

Age Calculator

Calculate exact age in years, months, and days from a birth date to a chosen date.

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Cooking

Alcohol Dilution Calculator

Calculate water needed to dilute spirits to a target ABV.

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Finance

Amortization Calculator

Build a month-by-month schedule of principal and interest payments.

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Unit Converters

Angle Converter

Convert angles between degrees, radians, and gradians.

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Home

Appliance Energy Calculator

Estimate monthly electricity cost for any appliance usage pattern.

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Finance

APR Calculator

Compare the true annual cost of a loan after interest and upfront fees.

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Finance

APY Calculator

See how compounding frequency changes the real yield on savings or CDs.

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Unit Converters

Area Converter

Convert area units for land, rooms, and material estimates.

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Construction

Asphalt Calculator

Estimate asphalt tonnage from area, thickness, and compaction factor.

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Education

Attendance Calculator

See how many classes you can miss before hitting an absence limit.

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Finance

Auto Loan Calculator

Estimate monthly car payments from vehicle price, rate, and term.

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Math

Average Calculator

Find the arithmetic mean, sum, count, minimum, and maximum of a list of numbers.

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Health

BAC Time Calculator

Estimate how long until blood alcohol returns to zero.

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Cooking

Baking Pan Converter

Adjust recipe amounts when switching pan sizes or shapes.

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Internet & Tech

Bandwidth Calculator

Estimate bandwidth needs from users, usage, and peak load.

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Internet & Tech

Base64 Encoder/Decoder

Encode or decode Base64 text for APIs and data transfer.

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Math

Binary Calculator

Convert numbers between binary and decimal formats.

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Date & Time

Birthday Countdown

See exactly how long until the next birthday celebration.

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Construction

Block Calculator

Estimate concrete block count for walls and foundations.

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Health

Blood Alcohol Calculator

Estimate blood alcohol level from drinks, weight, and elapsed time.

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Health

BMI Calculator

Calculate adult body mass index and its standard weight-status category from height and weight.

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Fitness

BMI Prime Calculator

Express BMI relative to the healthy reference range of 25.

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Health

BMR Calculator

Estimate basal metabolic rate from age, sex, weight, and height.

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Health

Body Fat Calculator

Estimate body fat percentage with the U.S. Navy circumference method.

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Fitness

Body Fat Percentage Calculator

Estimate body fat percentage from measurements and sex.

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Health

Body Surface Area Calculator

Calculate body surface area for clinical dosing and fitness metrics.

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Finance

Break Even Calculator

Find the sales volume needed to cover fixed and variable costs.

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Construction

Brick Calculator

Estimate brick count from wall area, brick size, and mortar gap.

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Date & Time

Business Days Calculator

Count working days between two dates excluding weekends.

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Business

CAC Calculator

Calculate customer acquisition cost from spend and new customers.

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Health

Calorie Calculator

Estimate daily calorie needs from age, sex, height, weight, and activity level using the Mifflin–St Jeor equation.

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Fitness

Calories Burned Calculator

Estimate calories burned by activity type, duration, and body weight.

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Real Estate

Cap Rate Calculator

Calculate capitalization rate from net operating income and value.

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Finance

Capital Gains Tax Calculator

Estimate federal and state tax on investment gains sold this year.

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Automotive

Car Loan Calculator

Estimate monthly car loan payments from price, rate, and term.

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Health

Carb Intake Calculator

Estimate daily carbohydrate needs from calories and macro split.

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Construction

Carpet Calculator

Estimate carpet square footage including waste for rooms and halls.

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Finance

Cash Flow Calculator

Compare cash inflows and outflows to see net operating cash flow.

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Real Estate

Cash-on-Cash Return Calculator

Measure annual cash return on cash invested in a property.

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Miscellaneous

Cat Age Calculator

Convert cat age to human years with a simple age curve.

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Business

Churn Rate Calculator

Measure customer churn from starting and lost accounts.

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Real Estate

Closing Cost Calculator

Estimate buyer closing costs as a percentage of purchase price.

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Cooking

Coffee Ratio Calculator

Dial in coffee-to-water ratio for consistent brewing strength.

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Miscellaneous

Coin Flip

Flip a virtual coin once or many times for random outcomes.

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Math

Combination Calculator

Count unordered selections when order does not matter.

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Finance

Commission Calculator

Calculate commission earnings from sales volume and commission rate.

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Finance

Compound Interest Calculator

Project investment growth with compound interest, recurring monthly deposits, and a chosen compounding frequency.

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