Cal.com API keys

Connect Cal.com with an API key from the account whose bookings and event types your workflows should manage. The key carries that user's permissions and remains valid until it expires or is revoked.

Prerequisites

You need a Cal.com account (cal.com cloud). Create the key from the account your workflow will use; check that its settings permit API access.

Cal.com API keys are tied to the user who creates them. For production workflows, create the key from a dedicated service login (e.g. sim-bot@yourcompany.com) rather than a personal account — the workflow identity is separate from an individual employee. Its access follows that account; keep it active.

Create the API key

1. 1

   Log in to Cal.com and go to Settings → Developer → API keys (direct link: app.cal.com/settings/developer/api-keys)

2. 2

   Click + Add, give the key a name (e.g. sim-workflows), and set its expiry. Choose the expiry appropriate for your workflows, or Never expires if available. Record any expiry date so you can rotate before it lapses

3. 3

   Copy the key when it's shown. Cal.com only displays it once — if you close the dialog, you'll have to create a new key.

Live-mode keys start with cal_live_; test-mode keys start with cal_. Either form is accepted.

Add the API key to Sim

1. 1

   Open Integrations from your workspace sidebar

2. 2

   Search for "Cal.com" and open it, then click Add to Sim and choose Add API key

3. 3

   Paste the API key, and optionally set a display name and description

4. 4

   Click Add API key. Sim verifies the key by calling Cal.com's /v2/me endpoint — if it fails, you'll see a specific error explaining what went wrong.

Use the credential in workflows

Add a Cal.com block to your workflow. In the credential dropdown, select the saved Cal.com API key. Configure the selected operation.

The block calls Cal.com's API (api.cal.com/v2) with the key. The credential acts as the Cal.com user who created the key — bookings, event types, and schedules the workflows touch are the ones that user can see and manage.

Expiry and rotation

If a key expires or is revoked, blocks using it fail authentication. Create a replacement in Settings → Developer → API keys. A credential Admin can open the connection in Sim's Integrations page, select Reconnect, and paste the replacement. Test a booking operation before deleting the old key. Sim does not refresh pasted API keys.

Use a cal_live_ key for production. A key accepted by /v2/me has passed an identity check; test-mode booking behavior and access to each booking or event type still need verification. Resource permissions follow the key's user, including whether that user hosts the booking.

Sim's Cal.com tools call api.cal.com; this credential cannot target a self-hosted Cal.com API host.

See Cal.com's API key setup for current settings and expiry controls.