Email verification API
Email verification that explains itself
99.5% target accuracy. Credits never expire. See why an address is deliverable, risky, or invalid.
100 free credits · No card required · Credits never expire
30-day money-back guarantee — On your first purchase, if you've used less than half your credits.
Try it live — verify a real email right now
Bulk Email Verification
Upload CSV or import from integrations
What is RocketVerifier?
RocketVerifier is an email verification API. It checks syntax, DNS and MX records, disposable and role addresses, catch-all domains, and the mailbox itself over SMTP. You get a deliverable, risky, or invalid result, plus the reason behind it, so you can clean a list or block a signup before it costs you a bounce.
Infrastructure
How email verification reaches the mailbox
Email verification has to talk to mail servers, not just a local database. RocketVerifier runs syntax, DNS, MX, disposable and role checks, catch-all detection, and an SMTP handshake so the verdict comes with a reason.
Multi-region SMTP network
Distributed SMTP verification network across multiple regions. Checks are routed toward the mail server being verified, which keeps SMTP handshakes reliable.
Direct Mail Server Communication
We talk to the mail server directly to confirm a mailbox exists, without sending a message that could hurt your reputation.
Rotating IP Architecture
Checks go out from rotating IPs across multiple providers, so mail servers keep accepting the handshake.
Constantly Updated Intelligence
Continuously updated database of tens of thousands of disposable domains, plus spam traps and role addresses, refreshed from public lists and our own detection.
Why infrastructure matters for email verification
Shared servers get blocked by Gmail, Outlook, and other providers, and a blocked checker cannot confirm a mailbox. Dedicated SMTP infrastructure is what keeps a 99.5% accuracy target realistic on live mail servers.
Deliverability
Why do verified lists bounce less?
A bounce tells mailbox providers the list is dirty. Removing invalid, disposable, and role addresses before you send is how teams keep bounce rates low and stay out of spam.
What Happens to Your Business
- High bounce rates destroy sender reputation
- Emails land in spam instead of inbox
- Wasted marketing budget on invalid leads
- ESP blacklisting threatens your domain
- Fake signups pollute your CRM
What You Get Instead
- Under 1% bounce rate protects reputation
- Higher inbox placement means more opens
- Only pay for real leads that convert
- Stay off blacklists permanently
- Clean, accurate CRM data always
How it works
How does email verification work?
Every address runs through the same seven checks, in order. Earlier checks are instant. The SMTP step confirms the mailbox exists and is the one that takes a second or two.
- 01
Syntax Check
RFC-compliant format validation
- 02
Domain Check
DNS and domain existence
- 03
MX Records
Mail server configuration
- 04
Disposable Detection
Block known temporary domains
- 05
Catch-All Check
Identify risky accept-all servers
- 06
Role Detection
Flag generic addresses
- 07
SMTP Verify
Mailbox existence proof
Features
Email verification features
Accuracy you can explain, credits that do not expire, a real-time API, a form widget, and SDKs for the stacks we actually ship.
99.5% Accuracy Guarantee
If an address we mark deliverable hard-bounces within 30 days, we refund 3× the credits spent verifying it.
Credits Never Expire
Pay-as-you-go credits never expire. Buy now, use whenever you need.
Real-time API
Real-time API, typically under half a second (SMTP checks 1–3s). Bulk lists up to 100,000 emails per job.
RocketShield Widget
Block bad emails at form submission with our JavaScript widget. Stop fakes before they pollute your database.
25+ Data Points
Get comprehensive insights: deliverability score, provider detection, risk assessment, and much more per email.
Official SDKs
Ready-to-use Node.js, Python, REST, MCP, and CLI. Integrate in an afternoon.
RocketShield
Stop fake signups at the form
Stop disposable and fake signups at the form. The JavaScript widget checks an address as it is typed, before it ever lands in your database.
- Block disposable emails, typos, and fakes before submit
- Set the rules that matter for your form
- One script tag on WordPress, Webflow, React, or plain HTML
<form id="signup">
<input type="email"
data-rocketshield="true"
placeholder="Enter email"
/>
<button>Sign Up</button>
</form>
<script src="rocketshield.js">
</script>Comparison
How RocketVerifier compares
Price, credit expiry, and what a typical pay-as-you-go verifier publishes. Their figures are vendor claims, not our measurements.
| Feature |  RocketVerifier | Typical verifier |
|---|---|---|
| Price per 100K emails | $269 | Often $400–$800 |
| Accuracy | 99.5% target | Vendor claim |
| Bulk jobs | Up to 100K | Varies |
| Credits expire | Never | Often 6–12 months |
| API response | Under 0.5s typical | Varies |
| Form widget | Included | Sometimes extra |
Use cases
Who uses email verification
The same check, four jobs: keep a campaign out of spam, stop a fake signup, clean a client list, or make sure an order email arrives.
Works with your stack
Native apps, plus thousands more via Zapier and Make
Pricing
Email verification pricing
Pay for credits, not a seat. Pay-as-you-go credits never expire. Monthly and yearly plans cost less per email and roll unused credits forward.
Guarantee
99.5% accuracy, with a credit refund
Any address RocketVerifier classifies "deliverable" that hard-bounces when you actually send to it, within 30 days of verification, qualifies for a refund of 3x the credits spent verifying that address.
FAQ
Email verification FAQ
Accuracy, speed, credits, the API, RocketShield, and how pricing works.
How accurate is RocketVerifier?
We target 99.5% accuracy with a 7-layer check: syntax, domain and MX, disposable and role detection, catch-all, and a live SMTP handshake. If an address we mark deliverable hard-bounces within 30 days, we refund 3× the credits spent verifying it.
Do credits expire?
No. Pay-as-you-go credits never expire. Monthly and yearly plans add a credit allotment each cycle, and unused credits roll over.
How fast is email verification?
Real-time API, typically under half a second (SMTP checks 1–3s). Bulk lists up to 100,000 emails per job.
Do you offer an API?
Yes. Node.js, Python, REST, MCP, and CLI, with webhooks and documentation. Built for high availability, with a public status page.
What is RocketShield?
RocketShield is a JavaScript widget that checks emails as they are typed into a form. It blocks disposable addresses, typos, and fakes before they reach your database.
How does RocketVerifier pricing work?
Buy credits once and use them whenever you need — they never expire. Monthly plans are about 15% off and yearly plans about 25% off. Both add credits every month, and unused credits roll over.
Start verifying emails today
100 free credits after a work-email application. No card required. Credits never expire.