Math Tools

Calculators for binary, octal, decimal and hex conversion, percentages, the gap between two dates, Unix timestamps both ways, BMI, and mortgage payments. Results update as you type, the formulas are written out on the page so each figure can be checked by hand, and nothing is sent anywhere.

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Math Tools

Timestamp Converter

Converts second and millisecond timestamps to dates and back, showing UTC and your local time together.

Math Tools

BMI Calculator

Computes BMI and its category from height and weight, in metric or imperial units.

Math Tools

Date Difference

Counts days, weeks, months and years between two dates, with an option to include both endpoints.

Math Tools

Mortgage Calculator

Compares equal-payment and equal-principal schedules with adjustable currency, term and rate, and localised amount formatting.

Math Tools

Number Base Converter

Converts between binary, octal, decimal, hex and any base from 2 to 36, using BigInt so large values stay exact.

Math Tools

Percentage Calculator

Common percentage questions — share, increase, decrease — as tabs: pick one and fill in two numbers.

Math Tools

Other categories

Utilities8 Image Tools11 Text Tools18 Design Tools21 Document Tools3 Network Tools4 Data Conversion19 Format & Minify14 Encode & Crypto18 Programming13

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