Use Case
Disposable emails, bot-generated accounts, domains registered yesterday — they're all gaming your free tier. One API call catches them at signup.
No credit card · No overage charges · Credits never expire
The problem
20-40%
of free trials are throwaway accounts
$0
revenue from disposable email signups
Inflated
metrics that mislead your roadmap
Every fake signup distorts your activation funnel, wastes onboarding emails, and costs you infrastructure. The fix takes one API call at registration.
How it works
5,400+ throwaway domains blocked. Updated regularly from open-source feeds. The list_updated field proves the list isn't stale.
Bot-generated locals like asdkjfh38274@ get classified by pattern: keyboard_sequence, repeated_chars, random_characters. Not just a boolean — a pattern type your rules engine can use.
Domains registered days ago are a red flag. The risk_flag field returns newly_registered (≤30 days) or young_domain (≤90 days). Fraud teams can set their own threshold on age_days.
Bot-generated patterns (auto-gen, crawler, scraper), toxic local parts, and known abuse domains. Catches the accounts that slip past disposable detection.
In practice
Response for signup8374@tempmail.org
{
"score": 5,
"verdict": "invalid",
"checks": {
"disposable": { "is_disposable": true, "list_updated": "2026-04-26" },
"gibberish": { "is_gibberish": true, "score": 22, "pattern": "random_characters" },
"domain_age": { "age_days": 12, "risk_flag": "newly_registered" },
"abuse": { "is_toxic": false, "type": null }
}
}Three independent signals confirm this is a throwaway account. The list_updated date proves your protection isn't running on a stale list from 2019.
const result = await fetch('/api/v1/verify', { ... })
if (result.checks.disposable.is_disposable ||
result.checks.gibberish.is_gibberish ||
result.checks.domain_age.risk_flag === 'newly_registered') {
blockSignup('This email address is not accepted')
}Comparison
| Feature | MailSentry | ZeroBounce | NeverBounce |
|---|---|---|---|
| Disposable detection | 5,400+ domains | Yes | Yes |
| Gibberish pattern classification | Yes — 5 pattern types | No | No |
| Domain age check | Yes — age_days + risk_flag | No | No |
| Abuse pattern detection | Yes | Limited | No |
| List freshness transparency | list_updated field | Not disclosed | Not disclosed |
| Free plan | 1,000/mo recurring | 100/mo | 1,000 one-time |
Competitor capabilities reflect publicly listed features as of April 2026. Details may vary by plan tier.