Quickstart

1. Get an API key

Sign up free and create a key from the dashboard under Keys. Every account starts with 100 verification credits.

2. Make a request

Send a GET request to the verify endpoint with the address you want to check:

curl https://api.correctinbox.com/v1/verify \
  -H "Authorization: Bearer $CORRECTINBOX_API_KEY" \
  -G --data-urlencode "email=jane@example.com"

3. Read the result

Every response includes a result state and a confidence score:

{
  "email": "jane@example.com",
  "result": "valid",        // valid | invalid | catch-all | unknown
  "confidence": 0.97,
  "free": false,
  "role_account": false,
  "has_mx_records": true
}

• valid — deliverable mailbox.
• invalid — no mailbox / no MX.
• catch-all — accept-all domain, resolved where possible.
• unknown — couldn't resolve; never a guessed valid.

You're only billed for billable results — never for unknown or duplicate verifications.