Date Difference Calculator

The Date Difference Calculator works out the precise duration between two dates, broken down into years, months and days, and it can also count the number of business days between them. Pick a start date and an end date and you get an exact span instantly, with no need to count across the calendar yourself.

Project managers tracking timelines, HR teams calculating notice periods and leave, and anyone planning around a deadline use it to avoid miscounting across months of different lengths and leap years. The business-day option is especially helpful for delivery estimates and any calculation where weekends should not be included.

The calculation happens entirely in your browser, so the dates you enter are never uploaded or stored. There is no install and no account required, which makes it a fast, private planning tool you can rely on whenever an accurate span between two dates matters. Everything is worked out locally, so the dates you compare are never sent to or stored on a server.