Free Calendar Sync Guide

How to Sync Your Calendars
For Free

Learn how to synchronize your Google and Outlook calendar events across multiple accounts with eido's free tier. No credit card required.

Getting Started with Free Calendar Sync

eido helps you keep your calendar events synchronized across multiple accounts—including both Google Calendar and Outlook—completely free. Whether you need to mirror your work calendar to a personal account, create a unified view of all your schedules, or selectively sync specific events, eido makes it simple.

1

Sign Up Free

Create your free account with Google or Microsoft

2

Connect Calendars

Link your Google or Outlook calendar accounts

3

Create Pipes

Set up sync connections between calendars

4

Sync Automatically

Events sync in real-time via webhooks

Free Tier Includes

  • Connect up to 2 calendar accounts
  • Create sync pipes between calendars
  • Real-time webhook synchronization
  • Busy Only mode (privacy-first sync)
  • Cross-provider sync (Google ↔ Outlook)
  • Bidirectional sync support

Upgrade to Pro for unlimited calendar connections, Full Details mode, keyword filters, regex filters, and custom title templates.

Core Concepts

Nodes (Calendar Accounts)

Each calendar account you connect becomes a "node" in your sync network. Nodes can be from Google Calendar or Outlook, and you can mix and match providers freely. Free tier supports up to 2 calendar connections.

Multi-Provider

Connect Google and Outlook calendars for free

Secure Storage

Tokens encrypted with AES-256-GCM

Auto-Refresh

Access tokens refresh automatically

Pipes (Sync Connections)

Pipes are directional connections that sync events from a source calendar to a target calendar. Events flow in one direction only—create two pipes for bidirectional sync.

Source
Target

Free Sync Topologies

1-to-N: One Source to Many

Sync events from a single calendar to multiple destinations. Perfect for broadcasting your work schedule to personal, family, or project calendars.

Available on Free Tier

N-to-1: Many Sources to One

Aggregate events from multiple calendars into a unified view calendar. Great for seeing all commitments in one place.

Available on Free Tier

Bidirectional Sync

Create two pipes (A→B and B→A) for full two-way synchronization. Events created in either calendar appear in both.

Available on Free Tier

Loop Prevention

Every event synced through eido is marked with an origin ID—the calendar that first synced it. This prevents the same event from bouncing back and forth infinitely, making bidirectional sync safe.

Bidirectional Sync is Safe

You can create two pipes (A→B and B→A) without worry. Events you create in A sync to B, events you create in B sync to A. Synced events won't loop back.

Free Pipe Configuration

Sync Modes

Full Details

Pro Only

Syncs all event info: title, description, location, attendees

Busy Only

Free

Shows only as busy time—keeps sensitive details private

Event Filters

Pro Feature: Event filtering (keywords and regex patterns) is available on Pro plans. Free tier supports Busy Only mode only.

Control exactly which events get synchronized using keywords and regex patterns. All filters are case-insensitive and check both title and description.

FilterDescription
Exclude KeywordsEvents with these words are skipped
Include KeywordsOnly events with these words sync
Exclude RegexEvents matching pattern are skipped
Include RegexOnly events matching pattern sync

Frequently Asked Questions

Is eido really free?+
Yes! eido offers a free tier that includes essential calendar synchronization features. You can connect your Google and Outlook calendars and create sync pipes without any payment or credit card required.
How do I sync Google Calendar with Outlook for free?+
Sign up for a free eido account, connect both your Google Calendar and Outlook accounts, then create a 'pipe' between them. eido will automatically sync events in real-time using webhooks.
Does eido support bidirectional sync?+
Yes! You can create two pipes—one from Calendar A to B, and another from B to A. Events you create in either calendar will sync to the other. eido's loop prevention ensures synced events don't bounce back infinitely.
Is my calendar data secure?+
Absolutely. eido encrypts all OAuth refresh tokens using AES-256-GCM encryption. All data is transmitted over HTTPS, and we never store your actual calendar events—only sync metadata to prevent duplicates.
Can I filter which events get synced?+
Free tier supports Busy Only mode, which syncs events as busy time blocks without revealing details. Keyword and regex filters are available on Pro plans. Upgrade to Pro to filter events by keywords or regex patterns.
What calendar providers does eido support?+
eido currently supports Google Calendar and Microsoft Outlook (including Office 365 and personal Microsoft accounts). You can sync between accounts of the same provider or across providers.

Ready to Sync Your Calendars for Free?

Get started in seconds. Connect your Google or Outlook accounts and create your first sync pipe—no credit card required.

Start Syncing Free