Free tool — 10 checks per day from this page. Need more? Get a free API key.
§ WHY IT MATTERS
Throwaway addresses break your funnel.
~5%
of signups on public forms use disposable domains
70%+
of disposable signups never return within 24 hours
<10ms
average API response time for a disposable lookup
§ USE CASES
Where disposable detection pays off.
Block fake signups
Reject disposable domains at registration to keep your user table clean and your activation metrics honest.
Protect trial abuse
Serial trial resetters use a new throwaway each time. A disposable check stops the loop at the door.
Lead quality gating
Gate high-value gated content (whitepapers, demos) on a non-disposable address to keep sales pipelines real.
Fraud prevention
Pair disposable detection with device fingerprinting — disposable domains are a top signal for account-creation fraud.
§ DEVELOPER API
Drop it into your signup flow.
POST the email, read is_disposable, decide. One call, one header, one JSON body. Works with any language that can hit an HTTPS endpoint.
curl -X POST https://api.bouncecheck.email/api/v1/verification/disposable-check \
-H "X-API-Key: YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{"email": "[email protected]"}'EXAMPLE RESPONSE
{
"email": "[email protected]",
"domain": "mailinator.com",
"is_disposable": true,
"checked_at": "2026-04-18T10:00:00Z"
}ENDPOINT
POST /api/v1/verification/disposable-check
AUTH
X-API-Key: <your-key>
§ FEATURES
Built for signup-time checks.
Millisecond lookups
Pure domain match. No SMTP, no DNS round-trip. Sub-20ms end-to-end.
Curated domain list
Thousands of known throwaway providers, refreshed as new ones appear.
Simple REST API
One POST call, JSON in, JSON out. Works with any language.
Free API key
50 calls/month on the free plan. No card, no trial. Upgrade when you need more.
Privacy-first
We don't store the emails you check. Only anonymized domain counters.
Designed for signup
Built for inline use in registration flows — reject, challenge, or allow.
§ THE PRIMER
What is a disposable email, really?
A disposable email (a.k.a. throwaway, temp-mail, burner mail) is a mailbox that exists for minutes or hours, then disappears. Providers like mailinator.com and 10minutemail.com let anyone generate one in a single click, confirm a signup, then walk away. The account on your platform becomes dead weight the moment the mailbox vanishes.
For product teams, disposable signups quietly wreck every top-of-funnel metric. Signup counts look healthy; activation, retention, and trial-to-paid crater. Growth dashboards lie. For fraud teams, disposable domains are one of the strongest signals in account-creation models — they correlate with referral abuse, trial resets, and coordinated fake-review attacks.
The fix is a single lookup at the door: before you write the user record, check whether the domain is on a known throwaway list. If yes, reject (or challenge with a harder step like SMS or OAuth). If no, proceed normally. Total latency: a few milliseconds. Total ongoing cost: effectively zero.
BounceCheck's disposable checker is designed exactly for that moment. It's a pure domain lookup — no SMTP connection, no MX query — so you can call it inline on every signup without slowing down your form. Pair it with full verification before outbound sends and you've covered both the inbound (fake signups) and outbound (dead addresses) sides of email hygiene.
§ FAQ
Disposable check FAQ
Everything about detecting throwaway email domains, the free API, and integrating it into your signup flow.
Still have questions? Contact us§ BLOCK THROWAWAY SIGNUPS
Get your free API key in 30 seconds.
Free plan: 50 calls a month, no card required. Upgrade any time.
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