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Test emails

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The test addresses
Credits
Example
What test addresses don't cover
Keep them out of production
Related

Test addresses return the same result every time, answer instantly, and don't use credits on the single and batch endpoints. Use them in development and CI to exercise each branch of your result handling.

The test addresses

These six always return a deliverable result:

Address	`status`	`category`	`failType`
`[email protected]`	`mailbox_found`	`deliverable`	`none`
`[email protected]`	`mailbox_found`	`deliverable`	`none`
`[email protected]`	`mailbox_found`	`deliverable`	`none`
`[email protected]`	`mailbox_found`	`deliverable`	`none`
`[email protected]`	`mailbox_found`	`deliverable`	`none`
`[email protected]`	`mailbox_found`	`deliverable`	`none`

The rest each return one specific outcome:

Address	`status`	`category`	`failType`	`statusMessage`
`[email protected]`	`mailbox_found`	`deliverable`	`none`	The mailbox exists and accepts mail.
`[email protected]`	`no_response`	`risky`	`temporary`	The mail server would not confirm this address.
`[email protected]`	`server_error`	`undeliverable`	`temporary`	The mail server returned an error.
`[email protected]`	`server_error`	`undeliverable`	`temporary`	The mail server returned an error.
`[email protected]`	`mailbox_not_found`	`undeliverable`	`permanent`	This mailbox does not exist.
`[email protected]`	`blocked_by_server`	`risky`	`temporary`	The mail server blocked the check.
`[email protected]`	`accept_all`	`risky`	`none`	The domain accepts mail for any address, so this mailbox can't be confirmed.
`[email protected]`	`mailbox_unconfirmed`	`risky`	`none`	The mailbox seems to exist, but the server would not confirm it accepts mail.
`[email protected]`	`disposable`	`risky`	`none`	This is a throwaway inbox that will likely stop working soon.

Watch the domains: [email protected] is deliverable, while [email protected] is a missing mailbox. Copy the full address. Matching ignores case, so [email protected] behaves like the lowercase form.

Credits

Single and batch: test addresses don't use credits and don't need a balance: a request made only of test addresses works with zero credits. Any other address in the same request still needs credits, which are reserved when the request arrives.
Bulk: every row in a CSV uses a credit, test addresses included.

You still need a valid API key. Test addresses skip the charge, not authentication, so they also confirm that your key and headers are right. They also count toward rate limits.

Example

Request

curl -G "https://simplecold.com/api/v1/api-validation/single" \
  --data-urlencode "[email protected]" \
  -H "Authorization: Bearer YOUR_API_KEY"

Response · 200

{
  "code": "SUCCESS",
  "message": "Successfully performed operation.",
  "payload": {
    "email": "[email protected]",
    "domain": "acceptall.com",
    "status": "accept_all",
    "statusMessage": "The domain accepts mail for any address, so this mailbox can't be confirmed.",
    "category": "risky",
    "failType": "none",
    "mxLocation": "US",
    "siteLocation": "US",
    "siteLanguage": "EN",
    "suggestion": null
  },
  "requestId": "5f3a..."
}

One batch request covers every branch:

Request

curl -X POST "https://simplecold.com/api/v1/api-validation/batch" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"emails":["[email protected]","[email protected]","[email protected]","[email protected]","[email protected]"]}'

What test addresses don't cover

processing results. Test addresses answer instantly. With a test key, slow@… answers processing and becomes final about 20 seconds later.
Typo suggestions. None of the test addresses return a suggestion. Any …@gmial.com address does, with live and test keys.
Rate limits and server errors. Test addresses still count toward your live rate limits. With a test key, error-429@… and error-500@… return those errors on demand, and sandbox traffic has its own limits.
Bulk jobs. Every row of a live CSV uses a credit. Sandbox bulk jobs are free.

The sandbox covers all of these without credits.

Keep them out of production