Instantly detect and block temporary, disposable, and burner email addresses in real-time with sub-50ms latency. Prevent fake account creation, reduce bounce rates, and protect your database at the point of signup.
const response = await fetch('https://api.fadsync.com/v1/verify', {
method: 'POST',
headers: {
'Authorization': 'Bearer fs_live_********************',
'Content-Type': 'application/json'
},
body: JSON.stringify({ email: 'user@tempmail.ninja' })
});
const data = await response.json();
if (data.is_disposable) {
console.warn('⛔ Access Denied: Disposable domain detected.');
}Stop fake users from destroying
your email reputation.
Disposable domains, burner inboxes, and malicious bot signups inflate your infrastructure costs and damage inbox deliverability. MailCheck API by FadSync provides developer-first, real-time email verification to keep your user database authentic.
Real-Time Disposable Detection
Block temporary email services, 10-minute mailboxes, and zero-day burner domains before they reach your database. Our continuously updated algorithms catch stealth disposable providers that static blacklists miss.
Learn moreDatabase & CRM Hygiene
Maintain clean user records and protect your mailing lists from invalid signups. Automatically reduce hard bounces, prevent SaaS free trial abuse, and improve email deliverability without manual review.
Explore integrationSub-50ms Edge Latency
Deploy synchronous email validation directly into your registration and checkout flows. Powered by an edge infrastructure optimized for sub-50ms global response times with zero onboarding friction.
View benchmarksIntegrate in minutes.
Secure forever.
A lightweight, RESTful email validation API designed to drop into any signup form, onboarding workflow, or backend stack. With ready-to-use SDKs for Node.js, Python, Go, and PHP, you can start detecting disposable email addresses with a single API request.
Loved by developers. Trusted at scale.
See how backend architects, SaaS founders, and engineering teams protect their user databases and signup pipelines with MailCheck API.
"Most email verification APIs add 400ms+ to our signup pipeline. MailCheck API responds in ~25ms from edge nodes. Zero perceptible latency during onboarding."
"We got hit with over 3,500 burner registrations during our Product Hunt launch week. We integrated MailCheck API in 10 lines of code and immediately stopped the spam surge."
"Cleanest JSON response format we've worked with. The is_disposable and MX detection flags are deterministic, accurate, and have handled 100k+ daily verifications with zero hiccups."
"Filtering out disposable domains at the moment of signup dropped our email bounce rates from 6.2% down to 0.8%, which protected our sender reputation across all ESPs."
"The in-memory, zero-retention verification policy was critical for our GDPR and security audit. Payload data is processed and instantly discarded without persistent logging."
"We were losing server resources to users recycling disposable emails to farm free trial credits. Adding MailCheck to our auth pipeline stopped multi-account abuse overnight."
Switching from a Legacy Provider?
Engineering teams are migrating to MailCheck API for sub-50ms edge latency, zero-retention privacy, and real-time disposable domain detection. Compare us head-to-head.
ZeroBounce Alternative
Stop waiting 400ms+ for validation. Switch to edge-native architecture that processes requests in RAM.
NeverBounce Alternative
Tired of paying for expensive monthly seat locks? Get 100% Zero-Retention privacy on a true pay-per-request model.
Hunter.io Alternative
Don't rely on probabilistic guessing that ruins your sender reputation. Upgrade to deterministic SMTP verification.
Predictable pricing for any scale.
Transparent, high-volume email validation pricing. Start for free, upgrade when you need to. No hidden fees, no surprises.
Basic
Perfect for testing real-time disposable email verification.
Pro
For growing SaaS apps needing automated burner domain blocking.
Ultra
High-velocity verification for scaling production apps.
Mega
Maximum throughput with enterprise SLAs and dedicated support.
Need something custom?
We offer tailored infrastructure solutions for specific industry requirements including healthcare (HIPAA) and finance (PCI-DSS) for volumes above 1M requests.
View full feature comparisonSOC2 Certified
Enterprise-grade security standards.
Global Edge
Presence in 40+ regions worldwide.
Everything you need to know.
Start blocking fake accounts in under 2 minutes.
Join thousands of developers and SaaS founders securing their databases against disposable bot signups. No credit card required to start.