New Playbook: Cold Email Infrastructure Setup Guide

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Free email verifier: real-time SMTP check, on this page

Paste any business email. Get a real SMTP verdict in under a second: deliverable, undeliverable, catch-all, or risky. No signup, no API key. 15 free checks per IP per day.

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mark_email_read Paste an email above to run an SMTP check.

What is email verification?

Email verification confirms an address is real and able to receive mail before you send to it. The standard method is an SMTP handshake: the verifier opens a connection to the recipient's mail server, asks if the address exists, and reads the answer without actually delivering a message. The whole round trip happens in well under a second.

Verification protects your sender reputation. Inbox providers (Gmail, Outlook, Yahoo) throttle senders whose bounce rate climbs above 2%. One bad list can put your domain in spam folders for weeks. Verifying before you send keeps bounce rate near zero.

What this verifier checks

dns

MX records

Confirms the domain has mail servers configured. No MX means no email is possible.

handshake

SMTP handshake

Connects to the mail server and asks if the mailbox exists, without sending a message.

filter_drama

Catch-all detection

Flags domains that accept every address. Catch-alls bounce silently or land in a black hole.

block

Disposable + role-based

Flags throwaway domains (mailinator, tempmail) and group addresses (info@, sales@) so you do not waste sends on them.

Why bounce rate matters

< 2%

Bounce rate threshold Gmail and Outlook tolerate before throttling.

30+ days

Recovery time from a deliverability drop caused by one bad bulk send.

99%

Mailsfinder's verified deliverability rate across SMTP-checked addresses.

Pricing

Free

$0

100 verified lookups per day, forever. No card.

Monthly

$9.99/mo

300,000 credits per cycle.

Lifetime

$249 once

2,000,000 credits, lifetime pool.

Frequently asked questions

How is this different from sending a test email? expand_more
A test email actually delivers and counts as a send. If the address bounces, your sender score takes the hit. SMTP verification opens the same conversation with the mail server but stops short of delivering, so no bounce is recorded against you.
What does "catch-all" mean? expand_more
A catch-all domain accepts every address sent to it, even ones that do not exist. The SMTP server returns "OK" regardless. Mail to a non-existent address either bounces later or is silently dropped. Catch-alls are flagged "risky" here so you can decide whether to send.
Why only 15 free checks per day? expand_more
Each SMTP check costs real compute and connection time, and we throttle to keep the tool free and fast for everyone. Sign up at app.mailsfinder.com for 100 free credits per day, no card. Bulk users start at $9.99 per month for 300K credits.
Can I verify Gmail or Outlook personal addresses? expand_more
Gmail and most large providers return ambiguous SMTP responses to anti-abuse callbacks, so the verdict on personal Gmail/Yahoo addresses is often "risky" or "unknown" by design. Business domains (G Suite / Microsoft 365 on a company domain) verify cleanly because they answer the handshake honestly.
Does the verifier store the emails I check? expand_more
No. Each request goes through a proxy that records only your IP for rate limiting, not the email itself. The verification call is stateless. For paid plans, history is stored in your account so you can re-export results.

Related reading

Deeper guides and comparisons worth bookmarking alongside this tool.

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Verify lists, not just one address

Sign up free for 100 daily credits, or upload a CSV and verify thousands in one go. No card required.

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