# API v1 stops working

Calls to /api/v1/* on Calendly API v1 stopped working on August 27, 2025.

On August 27, 2025, Calendly retired API v1, making all /api/v1/* calls no longer available. Any requests sent to these endpoints after this date fail. The shutdown also retires associated v1 webhooks.

## What to use instead

Migrate to API v2 using a personal access token or OAuth, as API v1 keys do not work with v2. Because v2 payloads differ from v1, moving requires updating your authentication setup and adapting your request and response structures.

API v1 keys do not work with v2: someone must create a personal access token or an OAuth app.

- API: Calendly API v1 (calendly.com)
- Kind: Version retirement
- Announced: March 26, 2025
- Takes effect: August 27, 2025
- Calls after that day: fail
- Calls it hits: `/api/v1/*`
- Source: [Announcement](https://developer.calendly.com/how-to-migrate-from-api-v1-to-api-v2)
- Verified: October 26, 2026, against Calendly API v1's own pages
- Page: https://www.okapi.bot/providers/calendly-api-v1/breaking-changes/api-v1-stops-working/

## Calendly API v1's words

> The v1 API and Webhooks have been retired as of 8/27/25 and are no longer available.

Okapi finds the calls this change hits in your repo and opens the pull request with the fix: https://github.com/apps/okapi-agent