What are API keys?
API keys are how you authenticate requests to the SendKit API. Every API call requires a valid key passed as a Bearer token in theAuthorization header.
Keys are scoped to your team — any key created by a team member has access to the team’s resources (emails, domains, contacts, etc.).
Creating an API key
Go to API Keys in the dashboard and click Create API Key.
After creation, the full key is shown once. Copy it immediately — you won’t be able to see it again.
Key format
All SendKit API keys follow the format:sk_ followed by 48 random characters (51 characters total).
Using your API key
Pass the key as a Bearer token in theAuthorization header on every API request. See the API Reference for examples and interactive testing.
For the Laravel SDK, just set the SENDKIT_API_KEY environment variable and you’re ready to go.
Expiration
API keys can be created with or without an expiration date:- No expiration — The key remains active until you delete it
- With expiration — The key automatically becomes inactive after the set date. Requests made with an expired key return a
401error
Security best practices
1
Use separate keys per environment
Create different keys for production, staging, and development. If a key is compromised, you only need to rotate one.
2
Set expiration for temporary access
If you’re sharing a key with a contractor or CI/CD pipeline, set an expiration date so it automatically stops working.
3
Never commit keys to source control
Store keys in environment variables or secret managers. Never hardcode them in your codebase.
4
Rotate keys periodically
Create a new key, update your application, then delete the old one. SendKit tracks
last used at so you can verify the old key is no longer in use before deleting it.Deleting an API key
You can delete an API key at any time from the dashboard. Deletion is immediate and irreversible — any application still using the key will start receiving401 errors.
Check the Last used column before deleting to make sure the key isn’t actively in use.
FAQ
How many API keys can I create?
How many API keys can I create?
There’s no limit. Create as many keys as you need for different environments, services, or team members.
Can I see the full key after creation?
Can I see the full key after creation?
No. The full key is only shown once at creation time. SendKit stores a secure hash, not the original key. If you lose it, create a new one.
What happens if I use an expired key?
What happens if I use an expired key?
The API returns a
401 Unauthorized error. Create a new key or remove the expiration from the existing one.
