Date difference calculator
Days, weeks, months and weekdays between two dates.
Pick two dates.
How it works
The calculator counts the days from the start date up to the end date. By default the end date itself isn't counted, so Monday to Friday is 4 days, the way you'd count nights or a countdown. Turn on include the end date to count both days, as you would for a holiday or a contract (Monday to Friday = 5 days).
Weekdays are Monday to Friday; bank holidays aren't taken off.
Worked example
From 1 January 2026 to 1 January 2027 is 365 days, which is 52 weeks and 1 day, or 1 year exactly. 261 of those days are weekdays.
Questions
Should I include the end date?
For "how long until" or a number of nights, no. For a period where both the first and last days count (a holiday, leave, a contract term), yes.
Does it account for leap years?
Yes. Every date is counted exactly, so a range that includes 29 February has the extra day.
Are bank holidays excluded from weekdays?
Not yet: weekdays here are Monday to Friday. A working-days calculator with UK bank holidays is planned.