Week Numbers

Week Numbers for the Year 2025

Knowing the week numbers for 2025 can be helpful for planning events, managing projects, or simply staying organized. Here’s a complete breakdown of all the weeks in 2025, including their start and end dates.

What Are Week Numbers?

Week numbers are a standardized way of counting the weeks in a year. Each week is assigned a number from 1 to 52 (sometimes 53), depending on how the calendar aligns with the start of the year. According to the ISO 8601 standard, each week starts on a Monday, and Week 1 is the week that contains the first Thursday of the year.

Week Number Table for 2025

Week NumberStart DateEnd Date
Week 1Dec 30, 2024Jan 5, 2025
Week 2Jan 6, 2025Jan 12, 2025
Week 3Jan 13, 2025Jan 19, 2025
Week 4Jan 20, 2025Jan 26, 2025
Week 5Jan 27, 2025Feb 2, 2025
Week 6Feb 3, 2025Feb 9, 2025
Week 7Feb 10, 2025Feb 16, 2025
Week 8Feb 17, 2025Feb 23, 2025
Week 9Feb 24, 2025Mar 2, 2025
Week 10Mar 3, 2025Mar 9, 2025
Week 11Mar 10, 2025Mar 16, 2025
Week 12Mar 17, 2025Mar 23, 2025
Week 13Mar 24, 2025Mar 30, 2025
Week 14Mar 31, 2025Apr 6, 2025
Week 15Apr 7, 2025Apr 13, 2025
Week 16Apr 14, 2025Apr 20, 2025
Week 17Apr 21, 2025Apr 27, 2025
Week 18Apr 28, 2025May 4, 2025
Week 19May 5, 2025May 11, 2025
Week 20May 12, 2025May 18, 2025
Week 21May 19, 2025May 25, 2025
Week 22May 26, 2025Jun 1, 2025
Week 23Jun 2, 2025Jun 8, 2025
Week 24Jun 9, 2025Jun 15, 2025
Week 25Jun 16, 2025Jun 22, 2025
Week 26Jun 23, 2025Jun 29, 2025
Week 27Jun 30, 2025Jul 6, 2025
Week 28Jul 7, 2025Jul 13, 2025
Week 29Jul 14, 2025Jul 20, 2025
Week 30Jul 21, 2025Jul 27, 2025
Week 31Jul 28, 2025Aug 3, 2025
Week 32Aug 4, 2025Aug 10, 2025
Week 33Aug 11, 2025Aug 17, 2025
Week 34Aug 18, 2025Aug 24, 2025
Week 35Aug 25, 2025Aug 31, 2025
Week 36Sep 1, 2025Sep 7, 2025
Week 37Sep 8, 2025Sep 14, 2025
Week 38Sep 15, 2025Sep 21, 2025
Week 39Sep 22, 2025Sep 28, 2025
Week 40Sep 29, 2025Oct 5, 2025
Week 41Oct 6, 2025Oct 12, 2025
Week 42Oct 13, 2025Oct 19, 2025
Week 43Oct 20, 2025Oct 26, 2025
Week 44Oct 27, 2025Nov 2, 2025
Week 45Nov 3, 2025Nov 9, 2025
Week 46Nov 10, 2025Nov 16, 2025
Week 47Nov 17, 2025Nov 23, 2025
Week 48Nov 24, 2025Nov 30, 2025
Week 49Dec 1, 2025Dec 7, 2025
Week 50Dec 8, 2025Dec 14, 2025
Week 51Dec 15, 2025Dec 21, 2025
Week 52Dec 22, 2025Dec 28, 2025
Week 53Dec 29, 2025Jan 4, 2026

Yes, 2025 has 53 weeks! This happens when the year starts on a Thursday or is a leap year that ends on a Thursday—allowing for that extra ISO week.

Why Are Week Numbers Useful?

Week numbers are used in a variety of scenarios across professional and personal settings:

Fun Fact

The ISO 8601 week-numbering system was first introduced in 1988 and is used by many countries around the world, especially in Europe. The U.S. doesn't commonly use it, but many global systems rely on it for consistency.

Find the Week Number of Any Date

Want to know the week number of a specific date? In PHP, you can use the DateTime object like this:

Week number is: 14

List the week numbers of the coming years.