Performance Optimization
PrimeCal is built to stay fast even with many calendars, recurring series, and automation rules — but a few habits keep things snappy as your workspace grows.
Keep Your Calendar Count Reasonable
Every calendar you subscribe to or own adds to what the month/week view has to render. If you're juggling a dozen calendars you rarely look at, consider:
- Archiving or deleting calendars you no longer need (see Deleting Calendars)
- Hiding calendars you keep for reference but don't check daily (toggle visibility instead of leaving everything on)
- Grouping related calendars so you can collapse whole groups at once
Be Selective With Automation Rules
Automation rules run on every matching event — a rule with broad triggers (e.g., event.created with no conditions) fires constantly. To keep evaluation fast:
- Add specific conditions so rules only evaluate when relevant (see Introduction to Automation)
- Remove or disable rules you're no longer using rather than leaving them active
- Check the audit log periodically — a rule firing far more often than expected is a sign its conditions are too broad
Limit Recurring Series Length
Recurring events with no end date generate occurrences indefinitely. When creating a recurring series, set an end date or occurrence count if the event won't truly run forever (a school class that ends with the semester, a project standup with a defined timeline).
Sync Settings
If you've connected external calendars (Google, Microsoft 365, Apple), syncing very large external calendars can slow your initial load. Where possible:
- Sync only the specific external calendars you need, not your entire external account
- Use the Free plan's single sync provider wisely — choose the one you actually check daily
Mobile and Offline
On mobile, offline mode caches your visible date range. Frequently jumping far into the past or future forces a fresh fetch — staying within a normal browsing range (a few weeks back and forward) keeps the app responsive.
Browser Tips (Web App)
- Keep your browser updated — PrimeCal uses modern web APIs for smooth rendering.
- If the calendar feels sluggish after a long session, a simple page refresh clears accumulated state.
- Browser extensions (ad blockers, privacy tools) occasionally interfere with calendar rendering. If you notice odd behavior, try disabling extensions one at a time to isolate the cause.