Date Calculator

What is the date calculator?

Working with dates often means answering questions like "how many days are left?" or "what is 45 working days from today?". This calculator does both locally in your browser: it measures the span between two dates and shifts a date forward or backward by days, weeks, months, or years.

Date range

Pick a start and end date to see the difference broken down into total days, weekdays (Monday to Friday), weekends, whole weeks, whole months, and whole years. If the end date is earlier than the start date, the calculator notes that for you.

Add or subtract

Choose a date, an amount, and a unit (days, weeks, months, or years), then add or subtract. Month and year shifts clamp overflow automatically, so January 31 plus one month lands on February 28 (or February 29 in a leap year) instead of rolling into March.

Privacy and limits

Everything is computed locally. Date math follows the Gregorian calendar and is timezone-independent, so results are stable no matter where you are.

What it is not

This tool works with calendar dates only. For Unix timestamps, use the timestamp converter; for current time across time zones, use the world clock.