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Every day, calculated.

Quick, accurate calculators for everyday questions. Type your numbers and see the answer instantly.

Calculators

14 tools

Percentage Calculator

Three everyday percentage questions, answered as you type.

Date Calculator

Count days between dates, or jump a number of days ahead.

Business Days Calculator

Working days between two dates, weekends taken out.

Week Number

Which ISO week it is, and which dates that week covers.

90 Days From Today

The date a set number of days ahead, and the same distance back.

Days Until Christmas

Live countdown to 25 December, in your own time zone.

Age Calculator

Your exact age in years, months and days.

Compound Interest Calculator

See how money grows when interest earns interest.

Unit Converter

Metric and imperial, converted as you type.

BMI Calculator

Body mass index from height and weight.

Discount Calculator

Sale prices and savings, worked out as you type.

Average Calculator

Paste your numbers, get mean, median and more.

Word Counter

Words, characters and reading time, live as you type.

Random Picker

Draw a winner or shuffle a list, fairly.

Guides

How to Calculate Percentages Without Getting Confused The three percentage questions people actually ask, how to solve each one, and the mental shortcuts that make discounts, tips and tax instant. What BMI Can Tell You, and What It Honestly Can't Where the body mass index comes from, why a 19th-century average became a personal health metric, what it is genuinely good for, and when it misleads. Compound Interest, Explained With Actual Numbers Why compounding starts slow and ends absurd, what the rule of 72 really tells you, how fees quietly reverse the effect, and the honest math behind it all. Days Between Dates: Why Date Math Keeps Surprising Everyone Fence-post errors, leap-year rules with two exceptions, months that refuse to be equal, and how deadlines actually count: the traps inside every date calculation.