Date Calculator
Week Number Calculator
Convert a date to its ISO week, or enter an ISO week to find its Monday-Sunday range.
Conversion
Result
ISO week1
ISO week year2026
Related Time Tools
Days Between Dates
Count calendar days between two dates.
Date Add/Subtract
Add or subtract days, weeks, months, and years.
Time Duration
Measure elapsed time across dates and time zones.
Weekday Calculator
Find the weekday, day of year, and ISO week for a date.
Age Calculator
Calculate exact age and milestone dates.
Date Patterns
Find same-calendar years and simple date facts.
Batch Dates
Add or subtract days from many dates at once.
Recurring Dates
Generate simple daily, weekly, or monthly date lists.