Weeks Calculator

Calculate weeks between dates, find week numbers, and manage project timelines with support for ISO week standards and business planning.

Weeks Calculator

Calculate weeks between dates or get week information for any date

Calculation Mode

Week Standard

Start Date

End Date

Project Week Management

Track project timelines and semester schedules in weeks

Project Name

Type

Start Date

End Date

Quick Add:

Key Features

Calculate weeks between any two dates

Get week number and ISO week for any date

Multiple week standards (Sunday, Monday, ISO)

Project timeline tracking and management

Academic and business planning tools

Copy-to-clipboard functionality

Understanding Week Standards

Sunday Start: US standard, week begins Sunday (common in North America)

Monday Start: European standard, week begins Monday (common in Europe)

ISO 8601: International standard, Monday start, Week 1 has 4+ days in January

Business Usage: ISO standard preferred for international business

Tips & Strategies

Project Planning: Use weeks for sprint planning and milestone tracking

Academic Scheduling: Track semester progress and assignment deadlines

Business Reporting: Use ISO weeks for consistent quarterly reporting

International Coordination: Use ISO standard for global team alignment

Agile Planning: Track sprints using 2-week iterations

Frequently Asked Questions

What is the difference between ISO and regular week numbers?

ISO 8601 weeks always start on Monday and the first week of the year is the one that contains at least 4 days of January. Regular weeks can start on Sunday or Monday depending on the standard.

How do I calculate project weeks?

Use the project management feature to add your project with start and end dates. The calculator will show total weeks, current week, and progress percentage.

Can I use this for academic planning?

Yes! The calculator is perfect for academic planning. Use semester presets or create custom academic periods to track weeks and progress.

What about partial weeks?

When calculating weeks between dates, the calculator shows both total weeks and remainder days for complete accuracy.

Which week standard should I use?

Use ISO 8601 for international business, Sunday start for US-focused projects, and Monday start for European contexts. Choose based on your audience and requirements.

How accurate is the week calculation?

The calculator uses the date-fns library for precise calculations and handles leap years, different month lengths, and week boundary edge cases accurately.

Can I track multiple projects simultaneously?

Yes! Add multiple projects with different start and end dates. The calculator tracks progress for each project independently and shows current week and completion percentage.

What are the common use cases for week calculations?

Project timeline management, academic semester planning, business quarter tracking, sprint planning, and any scenario requiring week-based time management.