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

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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%

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