ical4j
The premium Open Source alternative to Google Calendar API
🎯 Best for:Java applications requiring robust calendar data parsing and generation.
What is ical4j?
Replaces proprietary calendar parsing solutions for Java developers. It provides a comprehensive object model for RFC 5545 compliance and iCalendar file manipulation.
Tech Stack
JavaBackend & Auth
Why ical4j?
- • Industry standard for Java
- • Deep RFC compliance
- • Active maintenance
Limitations
- • Java only
- • Complex object model
- • Strict validation can be rigid
2/27/2026
Last Update
214
Forks
162
Issues
BSD-3-Clause
License
Financial Leak Detected
Stop the "SaaS Tax"
Your team could be burning cash. Switching to ical4j instantly boosts your runway.
Competitor Cost
-$1,440
/ year (est. based on Google Calendar API)
Self-Hosted
$0
/ year
Team Size10 Users
150+
SAVE 100%