How do I use Warmerly with an API?
Create an API key in Settings > Platform API keys, then send it in an X-Api-Key header
to https://app.warmerly.com/api/v1. API access comes with the Agency plan, and the
7-day Agency free trial includes it too, so you can test your integration before paying.
Everything the API does is also available in the dashboard. You only need a key when you want your own code, scripts or tools like Zapier to work with Warmerly.
Which plans include the API?
| Plan | API access |
|---|---|
| Free | No |
| Starter ($19/mo) | No |
| Growth ($49/mo) | No |
| Agency ($179/mo) | Yes |
| Agency 7-day free trial | Yes |
On any other plan, the Platform API keys page shows "API access is an Agency plan
feature" with an Upgrade to Agency button, and API calls answer 403 agency_plan_required. See Plans and limits for everything else each
plan includes.
Steps
-
Sign in to app.warmerly.com and open Settings > Platform API keys.
-
Under Create a key, type a name you will recognise later (for example "Production server" or "Zapier") and click Create key.
-
Copy the key straight away. It starts with
wmv_and is shown only once. If you lose it, revoke it and create a new one. -
Make your first request. Listing your keys needs nothing but the key itself:
Shellcurl https://app.warmerly.com/api/v1/keys \ -H "X-Api-Key: wmv_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"A working key returns
{ "keys": [ ... ] }with the key you just made in the list. -
Find your project ID. Mailboxes, campaigns and inbox data belong to a project, so most endpoints also need an
X-Project-Idheader. Get the ID fromGET /workspacesandGET /projects, or from the dashboard URL. -
Call a project endpoint, for example your mailboxes:
Shellcurl https://app.warmerly.com/api/v1/accounts \ -H "X-Api-Key: wmv_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx" \ -H "X-Project-Id: YOUR_PROJECT_ID"
From there, the API reference covers campaigns, leads, verification, inbox and webhooks.
Prefer an AI assistant to writing code?
Warmerly also has an MCP server, so ChatGPT, Claude and other assistants can work with your account directly. See Use with AI (MCP).
Common problems
401 unauthorized. The key is wrong, has a typo, or was revoked. Revoked keys stop
working immediately. Create a new key and try again.
403 agency_plan_required. The workspace is not on Agency (or an Agency trial). If you
just upgraded, allow about a minute for it to take effect. Keys are not deleted when a plan
changes, so they work again once the workspace is back on Agency.
400 "missing X-Project-Id header". The endpoint is project-scoped. Add the
X-Project-Id header. Authentication explains which endpoints need it.
429 too_many_requests. Each key has its own per-minute rate limit (60 requests a
minute by default). Slow down and retry. Limits for each endpoint are in
Errors and rate limits.
Related
- Authentication: headers, scopes and rate limits in detail
- API keys: create, list and revoke keys over the API
- Plans and limits: what Agency includes

