Validate any email. Detect fraud. Enrich the data.
MailRook Email Validation runs real-time deliverability checks, disposable & fraud detection, and full domain intelligence — one API, 99.9% accurate.
Checking syntax, MX, SMTP, trust, gateway, and domain profile…
A whole story behind every address.
Other validators reply with a flag. We open the envelope — deliverability, fraud risk, who runs the mail, what protects it, and how long the domain has existed. Built so a single check answers every question your team is about to ask.
- Decide
- Allow, challenge, or block — backed by a 0–100 trust score with itemised reasons.
- Send
- Know before you press send: gateway in front of the inbox, DMARC posture, catch-all behaviour.
- Enrich
- Domain age, registrar, ASN, MX provider, classification — every field a stable string in the API.
Will mail reach this inbox?
Messages scanned before reaching a person — expect stricter filtering.
Should you trust this signup?
Established domain · matched to a real business.
What kind of email is this?
Domain profile
Built for the question you came with.
Five teams reach the same widget for five different reasons. MailRook Email Validation answers the right one first — in the language that team already uses.
Stop the throwaway accounts that looked fine.
Decide at the form, not at the database. Trust scores tell you whether to allow, challenge, or block — before the row ever lands in your users table.
Signup protectionWarm the sending domain and segment this campaign — strict gateway filtering ahead.
See the gateway before you hit send.
Spot Proofpoint, Mimecast, Barracuda and seven more enterprise gateways via MX fingerprinting. Stop frying your domain reputation on prospects who were never going to receive cold mail.
Cold outreach deliverabilityCut bounce rate. Keep the sender reputation.
Upload a CSV, get every address back with a verdict, a score, and the reason. Sort, threshold, suppress — protect the domain you spent years warming up.
Email list cleaning{
"data": {
"email": "[email protected]",
"normalized_email": "[email protected]",
"domain": "stripe.com",
"mx_record": "aspmx.l.google.com",
"provider": "Google Workspace",
"result": "deliverable",
"score": 94,
"isv_deliverable": true,
"isv_nocatchall": true,
"isv_nodisposable": true,
"isv_nofreeemail": true,
"isv_nogeneric": true,
"protection_level": "enterprise",
"email_security": ["Proofpoint"],
"trust_score": 88
},
"code": 0, "message": "ok"
}▸ args: { email: "[email protected]" }
◂ result: deliverable · score 81 · company mailbox
The widget is the API response.
Every field rendered above is a stable JSON key in the API. Drop it into a signup endpoint or expose it to your AI agent via MCP — same shape, same names, no surprises.
We name the gateway nobody else names.
Most validators won't tell you what's protecting the inbox. MailRook Email Validation fingerprints 10 enterprise email gateways via MX records — so you know which prospects sit behind hard filtering before you send a single message.
Three ways to check an email.
On this page, as a CSV, or from your code. Same engine, same fields, same JSON in the response.
Paste one email.
Type or paste an address into the box at the top of this page. Answer in under a second. No signup.
Upload a list.
Drop a CSV with thousands of addresses. Download a cleaned file with a verdict and a score on every row.
Call it from your code.
One HTTP request from your app or signup form. Or one tool call from your AI agent over MCP.
curl api.mailrook.com/v1/validate/[email protected] \
-H "Authorization: Bearer …"Start free. Pay when you grow.
100 free checks every day — every account, forever. Add credits when you need volume. No subscription traps.
Perfect for developers and small teams getting started with email validation.
- 100 free checks per day
- Single & bulk email validation
- REST API access
- Syntax, DNS, MX & mailbox checks
- No credit card required
10,000 credits — use at your own pace. No subscription, no expiration.
- 10,000 verification credits
- Credits never expire
- Everything in the free plan
- One-time payment — no recurring fees
- $0.0039 per verification
For businesses and teams that need high-volume validation or dedicated infrastructure.
- Unlimited or high-volume checks
- Everything in the free plan
- Priority support
- SLA & dedicated infrastructure
- Custom integrations & onboarding
Frequently asked.
MailRook Email Validation performs multiple checks: syntax validation, DNS and MX record lookup, mailbox deliverability verification, catch-all detection, disposable email detection, and free email provider identification. Each check returns a separate flag so you can decide how strict your filtering should be.
Single email validations typically complete in under 500 milliseconds. Bulk list processing depends on list size, but most lists of up to 10,000 addresses finish within a few minutes.
No. MailRook Email Validation does not permanently store the email addresses you validate. Addresses are processed in memory and discarded after the validation result is returned. We are fully GDPR compliant.
A catch-all (or accept-all) domain is configured to accept emails sent to any address at that domain, even if the specific mailbox does not exist. This makes it impossible to confirm whether a particular address is real. MailRook Email Validation flags these so you can handle them separately.
Yes. Use the REST API to validate emails in real time as users sign up. A single GET request returns the full validation result, making it straightforward to block invalid or disposable addresses at the point of entry.
Yes. Every account gets 100 free email checks per day — no credit card required. This lets you validate emails, test the API, and explore all features before committing to a paid plan.
Yes. MailRook Email Validation detects 10 enterprise email security gateways including Proofpoint, Mimecast, Barracuda, Cisco, and FortiMail via MX record analysis. Every validation returns an email_security array listing detected gateways and a protection_level field (none, basic, or enterprise) — helping cold outreach teams prioritize unprotected inboxes for higher reply rates.
Your next email — checked.
100 free checks every day. No credit card. Be running in the time it takes to read this sentence.