Email validation API
One HTTP call, one JSON verdict. Syntax is a regex you could write yourself — what you pay for is the DNS lookup on the domain and a disposable-domain list that stays current, neither of which a form can do on its own.
The call
One endpoint for all four types. The key is generated in your dashboard and shown once.
curl -X POST https://data-checker.fr/api/v1/validate \
-H "Authorization: Bearer dck_live_…" \
-H "Content-Type: application/json" \
-d '{"type":"email","value":"contact@example.com"}'What the verdict covers
RFC 5322 syntax
Structure, allowed characters, total length capped at 254. It is the only part a regex gets right, and syntaxValid reports it separately from the overall verdict.
The domain's MX record
A DNS query from our servers, with a 4-second guard. With no MX and no fallback A record, no mail can be delivered: that is a guaranteed hard bounce, and it is invisible to any format check.
Disposable domains
Matched against a server-side list we keep current. Temporary-inbox services open new domains constantly; a list embedded in your code is stale within a month.
Role-based addresses
The roleBased flag marks contact@, info@, postmaster@ (RFC 2142). Make it a scoring criterion — automatic rejection costs you B2B leads.
What the API does not prove, and why
It does not say the mailbox exists. Knowing that would mean opening an SMTP connection and issuing RCPT TO — which we do not do: catch-all servers answer yes to everything, Gmail and Outlook deliberately return generic accepts to block account enumeration, and probing hundreds of addresses from one IP gets it listed on Spamhaus. A service promising certainty is selling confidence it does not have.
It also does not say your message will reach the inbox. Deliverability depends on your sender reputation, your SPF/DKIM/DMARC and your content. Validation removes hard bounces; it does not replace a correct sending setup.
Credits, not a subscription
One credit is one verification, whatever the type. You pay once, credits never expire, and nothing renews on its own.
Starter
9 €
1,000 verifications
0,009 € per verification
Growth
49 €
10,000 verifications
0,0049 € per verification
Scale
149 €
50,000 verifications
0,003 € per verification
Frequently asked questions
What does one verification cost?
One credit, whatever the type checked. Packs run from €9 for 1,000 verifications to €149 for 50,000 — €0.003 each at the best rate. One-off payment, no subscription, and credits never expire.
What is the latency?
Format checks answer in milliseconds. Email validation adds a DNS query: expect tens of milliseconds on a common domain, and at most 4 seconds on one that does not answer — past that, the domain is treated as having no MX rather than leaving your call hanging.
Is there a rate limit?
No per-minute quota: your credit balance is the only limit. For bulk work, call the API in a loop from your code, or use the list cleaner which does the same job over a whole file.
Is the checked data retained?
We log the check type, a truncated excerpt of the value and the verdict, for billing and your usage journal. Values are never resold, and hosting is in Europe.
Try it without a key first
The same check, in your browser, free and without an account — enough to confirm the verdict matches what you expect.
Email validator