I built a free REST API for week number calculations. No API key required, CORS enabled, runs on Cloudflare's edge network.
🚀 Quick Examples
GET /api/week → Current week
GET /api/week?date=2026-12-25 → Week for Christmas
GET /api/week?year=2026&week=53 → Date range for Week 53
📊 What I Built
The entire site has 18,000+ static HTML pages generated programmatically across 15 languages. All hosted on Cloudflare Pages free tier.
Features:
- 🗓️ Instant week number — Open the page, see today's week immediately
- 🌍 15 languages — Chinese, English, Japanese, Korean, Spanish, French, German, Portuguese, Russian, Arabic, Hindi, Thai, Vietnamese, Indonesian, Turkish
- 📡 Free JSON API — No API key needed, CORS enabled
- 🔧 Embeddable widget — Add week numbers to your website
- 🧬 Viral tools — Life in Weeks visualization, Birth Week calculator, Countdown timer, Week Comparison tool
- 📅 Printable calendars — Full-year week calendars
- 📘 ISO 8601 guide — Complete reference
- 🧩 Chrome extension — One-click week number
🛠️ Tech Stack
- Pure HTML/CSS/JS (no framework)
- Cloudflare Pages + Functions for the API
- Programmatic SEO with structured data (hreflang, BreadcrumbList, FAQ schema)
- 10+ interactive tools
🔗 Links
- Website: weeknumber.cc
- API Explorer: weeknumber.cc/api-explorer.html
Would love feedback from the dev community! 🙏
Top comments (0)