Sub-millisecond desktop calendar with zero cloud middlemen.
RapidCal is a local-first, cross-platform desktop calendar built by
CodeStacx. Connect your Google Calendar and
Microsoft Outlook / 365 accounts directly from your computer with
<1ms UI latency, offline SQLite WAL storage, and OS Keychain encryption.
Engineered for Speed, Precision & Privacy
Unlike Electron wrappers or cloud-proxied calendar apps that copy your schedule onto third-party servers, RapidCal runs natively on your machine and talks directly to Google and Microsoft APIs.
Offline-First SQLite WAL + FTS5
Events and recurring rules are indexed locally in SQLite with Write-Ahead Logging and FTS5 virtual
tables. Search thousands of events in under 2ms and edit schedules offline with an
optimistic outbox queue.
Direct Loopback OAuth2 + PKCE
Authentication uses a local loopback listener (127.0.0.1) with RFC 7636 PKCE
(S256). Your OAuth tokens never pass through any CodeStacx server and are sealed in your OS
Keychain + AES-256-GCM vault.
Google Calendar & Outlook Delta Sync
Incremental background synchronization powered by Google Calendar v3 nextSyncToken and
Microsoft Graph @odata.deltaLink, complete with bi-directional RFC 5545 RRULE
translation.
Cross-Account Busy Blocking
Automatically mirror personal events as redacted [Busy] blocks onto your work calendar
across Google Calendar and Microsoft Outlook so colleagues never double-book your time.
1-Click Video Meeting Join
Press Cmd/Ctrl + J from anywhere to immediately launch the active or upcoming Google Meet,
Microsoft Teams, Zoom, or Webex call without hunting through email invites.
Keyboard-First Command Palette
Press Cmd/Ctrl + K or C to create events with RapidCal's built-in Rust natural
language parser (e.g., "Team Sync tomorrow 2pm to 2:45pm"), switch views, or jump to any date.
How RapidCal Handles Your Google & Microsoft Data
Full transparency into the permissions RapidCal requests and how your calendar information is protected on your device.
RapidCal's use and transfer to any other app of information received from Google APIs will adhere to the Google API Services User Data Policy, including the Limited Use requirements. RapidCal operates zero external cloud servers: your calendar data is stored exclusively on your local computer, is never sold or shared with third parties, is never used for advertising, and is never used to train AI/ML models.
| Provider & OAuth Scope | Data Accessed | Why RapidCal Needs It |
|---|---|---|
Google Sign-Inopenid, email, profile
|
Email address, display name, and profile avatar URL. | Identifies your connected Google account in RapidCal's sidebar and account switcher when multiple calendars are linked. |
Google Calendar API v3https://www.googleapis.com/auth/calendar
|
Calendars, events, recurrence rules, attendees, RSVP status, and conference links. |
Enables two-way calendar sync, local offline search, creating/editing/deleting events, responding to
meeting invitations, and optional cross-account [Busy] blocking.
|
Microsoft Graph APIUser.Read, Calendars.ReadWrite, offline_access
|
Outlook / Microsoft 365 profile, calendars, and calendar events. | Enables two-way synchronization and event management for connected Microsoft Outlook and Microsoft 365 accounts. |
Built for Keyboard Velocity
Navigate your entire schedule without touching the mouse.
| Shortcut | Command |
|---|---|
Cmd/Ctrl + K |
Open Command Palette (Natural Language Quick-Add & Instant FTS5 Search) |
Cmd/Ctrl + J |
1-Click Join Active or Upcoming Video Meeting (Google Meet, Teams, Zoom, Webex) |
Cmd/Ctrl + R |
Trigger Immediate Incremental Delta Sync & Outbox Flush |
C |
Quick-Add Event with Rust Natural Language Parser |
D / 3 / 5 / W / M / A |
Switch to Day, 3-Day, Work-Week (5d), Week (7d), Month, or Schedule Agenda View |
T |
Jump to Today |