SaaS
Email Validation for SaaS — Block Fake Signups & Disposable Emails
Stop disposable email abuse on your signup forms, protect your trial metrics, and ensure onboarding emails actually reach real users.
End-to-End Protection
Your complete email quality pipeline
From signup to send, Mailchk protects every stage of your email lifecycle. Block bad addresses, clean your lists, score deliverability, and verify inbox placement.
Block at the Gate
Real-time signup protection
Stop fake, disposable, and scam emails the moment a user hits your signup form. Our API responds in under 50ms — before the page even finishes loading.
Clean Your Lists
Bulk CSV validation & catch-all testing
Already have an email list? Upload it and we'll scrub out the fakes, catch-all addresses, and dead mailboxes. Validate thousands of emails in minutes, not hours.
Score Every Email
Risk & deliverability scoring
Get a 0-100 deliverability score and risk level for every address. Prioritize your safest contacts and flag the risky ones before they damage your sender reputation.
Test Inbox Placement
Know where your emails land
Send a test email and see exactly where it ends up — Primary inbox, Promotions, Spam, or blocked entirely. Test across Gmail, Outlook, and Yahoo before you hit send on your campaign.
Test & Capture
Inspect every email your app sends
Create disposable test inboxes and send your transactional or marketing emails to them. Inspect the full content — HTML rendering, headers, attachments, and plain text — before going live.
Protect your platform at every stage of the email lifecycle
<50ms
API Response Time
470K+
Scam Domains Tracked
0-100
Risk Score Range
99.9%
API Uptime
Live Preview
See Signup Protection in Action
Watch how mailchk blocks disposable emails, catches domain typos, and validates real users at the point of signup.
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The Problem
Why Fake Signups Are Costing Your SaaS Money
Every fake signup wastes resources, skews data, and degrades the experience for real users.
Fake Trial Signups
Users create accounts with disposable emails to abuse free trials repeatedly, inflating your user count with zero conversion potential.
Inflated Metrics
Invalid emails skew your activation, engagement, and conversion metrics — making it impossible to measure real product-market fit.
Bounced Onboarding Emails
Welcome sequences and activation emails bounce, leaving new users without the guidance they need to convert to paid.
Disposable Promo Abuse
Bad actors use disposable emails to claim referral credits, discount codes, and promotional offers multiple times.
Capabilities
Everything You Need to Protect Your Signup Flow
A complete email validation toolkit built for SaaS registration forms, trial signups, and user onboarding.
Real-Time API Validation
Validate emails at signup in under 50ms. Sub-second response times keep your registration flow fast and frictionless.
Disposable Email Detection
Block 470,000+ known disposable and temporary email domains. Our AI discovers new ones daily before they hit your forms.
Domain Typo Detection
Catch common domain typos like gmial.com and offer "Did you mean gmail.com?" suggestions to recover real users.
Risk Scoring (0-100)
Every email gets a deliverability score from 0-100 based on syntax, DNS, domain reputation, and provider analysis.
Role Account Detection
Flag role-based emails like info@, admin@, support@ that signal shared inboxes with lower engagement and conversion rates.
Domain Authentication
Verify SPF, DKIM, and DMARC records to ensure the sending domain is properly configured for email delivery.
Recommended Products
Email Validation Tools for SaaS
Choose the right tool for your signup flow, from real-time API validation to bulk list cleaning.
Email Validation API
Block disposable and invalid emails at signup in real-time with sub-50ms response times.
Explore APIForm Guard
Add inline validation to your signup forms with zero backend work. Just a script tag.
Explore Form GuardEmail List Validation
Clean your existing user database. Upload a CSV and get detailed validation results.
Explore List ValidationInbox Placement Testing
Test where your onboarding emails land — Primary, Promotions, or Spam.
Learn MoreDon't just take our word for it
See why teams rely on Mailchk to keep their email lists clean
"Mailchk reduced our fake signups by 89%. The API is incredibly fast and the documentation is excellent."
Noel S
CTO, MyBrands Group
"We integrated Mailchk in under an hour. It catches disposable emails that other services miss."
Stephen M
Lead Developer, TRTCompare
"Finally, a solution that actually works. Our email deliverability improved by 40% after implementing Mailchk."
Michael G
Product Manager, Evernu
"The real-time validation is a game changer. No more wasted resources on fake accounts."
Joe S
Founder, Moojority
"Mailchk handles our 100k+ daily validations without breaking a sweat. Incredible performance."
Katie E
DevOps Lead, CVS
"Switched from a competitor and never looked back. Better accuracy, better pricing, better support."
Brendan O
Tech Lead, CardGenr
"Mailchk reduced our fake signups by 89%. The API is incredibly fast and the documentation is excellent."
Noel S
CTO, MyBrands Group
"We integrated Mailchk in under an hour. It catches disposable emails that other services miss."
Stephen M
Lead Developer, TRTCompare
"Finally, a solution that actually works. Our email deliverability improved by 40% after implementing Mailchk."
Michael G
Product Manager, Evernu
"The real-time validation is a game changer. No more wasted resources on fake accounts."
Joe S
Founder, Moojority
"Mailchk handles our 100k+ daily validations without breaking a sweat. Incredible performance."
Katie E
DevOps Lead, CVS
"Switched from a competitor and never looked back. Better accuracy, better pricing, better support."
Brendan O
Tech Lead, CardGenr
Reduce Fake Trial Signups Starting Today
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