Free email deliverability API
Simple JSON endpoints for SPF, DKIM, DMARC, blacklist and MX checks — no key required (rate-limited per IP).
Endpoints
GET https://mailspamchecker.com/api/spf?domain=example.com
GET https://mailspamchecker.com/api/dkim?domain=example.com&selector=default
GET https://mailspamchecker.com/api/dmarc?domain=example.com
GET https://mailspamchecker.com/api/blacklist?q=203.0.113.10
GET https://mailspamchecker.com/api/mx?domain=example.com
GET https://mailspamchecker.com/api/result/<token>
GET https://mailspamchecker.com/api/dkim?domain=example.com&selector=default
GET https://mailspamchecker.com/api/dmarc?domain=example.com
GET https://mailspamchecker.com/api/blacklist?q=203.0.113.10
GET https://mailspamchecker.com/api/mx?domain=example.com
GET https://mailspamchecker.com/api/result/<token>
Example
curl "https://mailspamchecker.com/api/dmarc?domain=github.com"
Each tool endpoint returns a JSON object with status (good / warn / bad / info),
a summary, and a list of lines. The /api/result/<token>
endpoint returns the full spam-test report once scored (HTTP 202 while still pending).
Rate limit: 120 requests/hour per IP. Need higher volume or a commercial plan? Get in touch.