# WhichWeek — Know your ISO week instantly

> Know your ISO week instantly (iPhone/iPad app by Arthur Kahwa.)

- Source: https://appshunter.io/ios/app/whichweek/id6761823162 (this page in markdown: same URL + `.md`)
- Developer: [Arthur Kahwa](https://appshunter.io/developer/1494643030)
- Category: Productivity
- Price: Free
- Age rating: 4+
- Requires: iOS 26.4 · 3 MB
- Languages: American English, Arabic, French (France), German (Germany), Italian, Japanese, Korean, Brazilian Portuguese, Chinese (Simplified, China), European Spanish
- Released: 2026-04-15
- Data updated: 2026-06-10
- User reviews in markdown: https://appshunter.io/ios/app/whichweek/id6761823162/reviews.md

## What is WhichWeek?

WhichWeek is the fastest way to know your ISO week number.

Open the app and your current ISO week number is front and center — bold, clear, and impossible to miss. No digging through a calendar. No mental arithmetic. Just the week number.

WEEK VIEW
• Your current ISO week number, large and legible
• The exact date range for that week (Monday to Sunday)
• Step forward or back through weeks and years with the stepper controls
• Tap Today to jump straight back to the current week
• Leap year indicator so you never lose track of the extra day

DAYS VIEW
• Pick any two dates and instantly see the number of days between them
• Broken down into full weeks and remaining days
• Perfect for project planning, countdowns, and date arithmetic

DESIGNED WITH CARE
• Pure SwiftUI — fast, native, and responsive
• Supports Dynamic Type for accessibility
• Full Dark Mode and Light Mode support
• Works in portrait and landscape
• Available on iPhone, iPad, Mac, and Apple Watch

ISO WEEK NUMBERS
ISO 8601 defines week numbering used widely in business, finance, logistics, and project management across Europe and beyond. Week 1 is the week containing the first Thursday of the year. WhichWeek follows this standard precisely.

NO ADS. NO TRACKING. NO SUBSCRIPTIONS.
WhichWeek is a one-time purchase. No accounts required, no data collected, no network requests made.


## Version history (last 1 release)

### 1.0 — 2026-04-15

No release notes.

## More apps by Arthur Kahwa

- [This Calendar Week](https://appshunter.io/ios/app/this-calendar-week/id1495557925)
- [MeetCost – Meeting Timer](https://appshunter.io/ios/app/meetcost-meeting-timer/id6758670965)
- [PDHD — Dialysis Companion](https://appshunter.io/ios/app/pdhd-dialysis-companion/id6761768841)

All apps by Arthur Kahwa: https://appshunter.io/developer/1494643030

---

*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-06-10.*