Cal.com API Keys

Cal.com service account credentials let your workflows authenticate to Cal.com with a pasted API key instead of a personal OAuth connection. The key carries the full permissions of the Cal.com user who created it, and it stays valid until it expires or is revoked — no OAuth consent to renew.

Prerequisites

You need a Cal.com account (cal.com cloud). Any user can create API keys from their own settings — no admin role required.

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 credential then survives any individual employee leaving, and bookings and event types the workflows manage belong to the bot user.

Creating the API Key

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

Click + Add, give the key a name (e.g. sim-workflows), and set its expiry. Choose a non-expiring key if the option is available — otherwise pick the longest expiry offered and note the date so you can rotate before it lapses

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.

The API key carries the full privileges of the user who created it — there is no scope selection. Treat it like a password: do not commit it to source control or share it publicly. Sim encrypts the key at rest.

Adding the Service Account to Sim

Open your workspace Settings and go to the Integrations tab

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

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

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.

The key is encrypted before being stored.

Using the Service Account in Workflows

Add a Cal.com block to your workflow. In the credential dropdown, your Cal.com service account appears alongside any OAuth credentials. Select it and configure the block as you normally would.

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.

Common Questions

API keys don't require any user to sit through a consent flow, and they stay valid until they expire or are revoked — which is what you want for an automated workflow. OAuth connections are tied to one person's session and consent.

No — a key carries the full permissions of the user who created it. There's nothing to select at creation time, and no Cal.com block in Sim can fail for missing scopes. Permission errors only arise from resource ownership, e.g. confirming a booking the key's user doesn't host.

Workflows using the credential start failing with authentication errors. Create a new key from the same Cal.com account, update the credential in Sim, and delete the expired key. If you couldn't create a non-expiring key, set a reminder before the expiry date you chose.

It will validate, but test-mode keys may not behave like live keys on booking operations. Use a cal_live_ key for production workflows.

No — Sim's Cal.com blocks call the cal.com cloud API (api.cal.com). Self-hosted Cal.com instances expose their own API host and are not supported by this credential.

Create a new key from Settings → Developer → API keys, update the credential in Sim with the new key, and once it's working, delete the old one in Cal.com.