Date, Time & Math

Timestamps

Translate Unix seconds or milliseconds into readable dates and compare a moment across selected IANA time zones.

Unix Epoch Seconds and Milliseconds ConverterConvert integer Unix timestamps to UTC, local, and ISO dates, or turn a browser-local date and time into epoch seconds and milliseconds. Essential for developers debugging APIs, parsing JWT claims, analyzing logs, and correlating events across systems that use different time representations.Date, Time & Math / TimestampsTry it

IANA Time Zone Comparison MatrixAnchor one browser-local date and instant, compare it across UTC and selected IANA zones, switch between live/manual time, and align the shared instant by a target-zone hour. Essential for remote teams scheduling meetings, developers debugging time-sensitive APIs, and travelers planning across zones.Date, Time & Math / TimestampsTry it

Converters

Convert values between compatible length, mass, temperature, area, volume, speed, and other measurement units.

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Unit Converter WorkbenchConvert length, mass, temperature, volume, speed, binary-labeled data storage, and fixed-duration time values, compare every unit in a category, and keep optional local history. Essential for engineers, students, and professionals performing quick dimensional analysis without looking up conversion factors.Date, Time & Math / ConvertersTry it

Time

Calculate the calendar and elapsed difference between two dates with clear sign, unit, and boundary handling.

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Date Difference, Age and Business-Day CalculatorCompare local calendar dates in four modes: elapsed date span, age to today, countdown to a target date, or weekday count including both endpoints. Useful for HR teams calculating tenure, project managers tracking deadlines, and anyone needing precise business-day arithmetic without timezone complications.Date, Time & Math / TimeTry it

General

Calculate a percentage, percentage change, or the base value behind a percentage with transparent arithmetic.

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Percentage CalculatorPercentage Calculator evaluates basic, change, reverse, and percentage-of-number formulas from the numeric values entered in the selected mode. Essential for students, accountants, business analysts, and anyone performing common percentage calculations without a spreadsheet.Date, Time & Math / GeneralTry it

Are these tools private and available offline?

Processing happens locally in browser memory. After the application has been cached, supported tools can continue working offline without sending your input to a server.