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Time & Date Calculators

Work out durations, countdowns, ages, and time-zone differences — instantly and privately.

These free time and date calculators answer the everyday “how long” and “what date” questions: your exact age, the days between two dates, a countdown to an upcoming date, the result of adding or subtracting days, hours worked, and the time in another zone. Each one shows its method and a worked example, so the result is never a black box.

Every calculation runs entirely in your browser using your device's local date and time — nothing you enter is uploaded or stored. They're calendar-correct and leap-year aware, so the numbers hold up for planning deadlines, anniversaries, projects, and travel.

6 time & date calculators

Frequently asked questions

Which calculator should I use to count down to a date?

Use the Days Until Calculator for a countdown from today to a single date. To measure the span between two specific dates, use the Date Difference Calculator; to shift a date forward or backward by a number of days, use the Date Calculator.

Are these date calculators leap-year accurate?

Yes. They work on real calendar dates, so leap years and the differing lengths of each month are handled automatically. Date handling is local-time based, so results don't drift by a day across timezones.

Do these calculators store the dates I enter?

No. Every calculation happens locally in your browser; the dates and times you enter are never uploaded, logged, or stored on a server.

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