Email
apiKeyHTTPSNo CORS
Email
PostStack
EU-hosted email API for transactional and marketing email, with contacts, broadcasts, and analytics.
PostStack API is a free Email API that requires apiKey authentication, is served over HTTPS and does not support CORS, so it should be called from a server.
- Authentication
- apiKey
- HTTPS
- Yes
- CORS
- No
- Category
Visit documentation ↗poststack.dev
About PostStack
Guides and API reference for PostStack: send your first email, verify domains, webhooks, rate limits, pagination, idempotency, SMTP, SDKs and MCP.
- Provider
- PostStack
- Website
- poststack.dev ↗
Details from poststack.dev.
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PostStack API FAQ
Who provides the PostStack API?
The PostStack API is provided by PostStack (poststack.dev). Guides and API reference for PostStack: send your first email, verify domains, webhooks, rate limits, pagination, idempotency, SMTP, SDKs and MCP.
Is the PostStack API free?
Yes. The PostStack API is listed in the Email category of the public-apis directory, which only includes APIs that are free or have a free tier. Check its documentation for rate limits and paid plans.
Does the PostStack API require an API key?
Yes. The PostStack API uses apiKey authentication, so you need to register for credentials before making requests.
Can I call the PostStack API from the browser?
Not directly. The PostStack API does not allow CORS, so call it from a server, serverless function or proxy instead of front-end JavaScript.
Does the PostStack API support HTTPS?
Yes. The PostStack API is served over HTTPS, so it's safe to use in production.