If you have ever had to coordinate a deadline for “Week 42,” you know the pain of converting that number into an actual date. This calculator is your quick-reference sheet for all things weekly. It instantly tells you the ISO-standard week number for any date you choose.

The Only Calendar Tool Project Managers Need

1. Fast Input: Three Ways to Get Started

You have quick options to find your week number instantly.

• Quick Buttons: Click “Today” or “Tomorrow” to instantly load and calculate the current or next day. This is the fastest way to use the tool.
• Date Picker: Click the “Select Date” field to open the calendar picker. Choose any date you need to track.
• Action: Click the green “Find Week Number” button. The result panel appears instantly.

Relatable: Knowing the week number is essential for scheduling work, planning sprints, or managing academic deadlines. This tool removes the guesswork that happens every January.

2. Read the Main Result

The big red box shows you the most important number: the week number itself.

• Week Number: This large number is the official week number of the year for the date you entered, like Week 50.
• Total Weeks: The smaller text reminds you that this is one week out of 52 total weeks in the year.

3. Check the Detailed Breakdown

The boxes below the main result give you all the context you need about that specific date and its surrounding week.

• Date and Day of Week: Confirms the exact date and weekday you selected.
• Day of Year: This shows how many days have passed since January 1st, another useful metric for planning.
• Week Range: This is the best part: it clearly lists the Week Starts (Monday) and Week Ends (Sunday) for that specific week number. This confirms the entire period the week number covers.

Use this to confirm project timelines, plan deliveries, or simply impress your team with your accurate scheduling knowledge.