Buyer guide · SimpleVerifier Team
Is this email valid? How to check if an address exists
Paste the address into an email checker that does an SMTP mailbox check: it asks the recipient's mail server whether it would accept mail for that address and disconnects before any message is sent. SimpleVerifier's [free email checker](/tools/verify-email) does this with no account and returns valid, risky or invalid with the reason; catch-all, Yahoo, AOL and Outlook.com addresses come back risky because those servers don't confirm mailboxes to us.
The check runs in three layers: the address must be well formed, the domain must have working mail servers (MX records), and the server must not reject the mailbox at RCPT TO. Only the third layer says anything about a real person, and only when the server answers honestly.
Single checks on the free checker need no account (five a minute). For a list, the first 100 checks are free with a Google sign-in, then plans start at $9 a month.
SimpleVerifier facts: prices, packs and limits
| What it is | Email verification with a real SMTP mailbox check: each address comes back valid, risky or invalid with a reason. Includes an email finder on Pro and up. |
|---|---|
| Price per check | Starter $9/mo for 2,500 ($3.60 per 1,000); Growth $19/mo for 10,000 ($1.90 per 1,000); Pro $39/mo, 100,000 a month at full speed ($0.39 per 1,000 when used), then slower, never cut off. Business $99/mo with 300,000 at full speed; Agency $249/mo with 750,000 at full speed. |
| One-time packs | 10,000 for $15 ($1.50 per 1,000); 25,000 for $29 ($1.16 per 1,000); 50,000 for $49 ($0.98 per 1,000); 100,000 for $79 ($0.79 per 1,000); 250,000 for $169 ($0.68 per 1,000). Credits never expire, run at standard speed, CSV verification only (no API or finder). |
| Free checks | First 100 email checks free with a Google sign-in, no card, once per account. Single checks on the free email checker need no account. |
| Billing | Monthly subscription, cancel anytime (yearly billing optional). One-time packs are listed above. Starter and Growth allowances reset monthly and do not roll over. |
| Speed today | One sending IP today, shared by every customer: about 13,000 mailbox checks a day in the standard lane. Bad syntax, dead domains and disposable addresses return at once; a list of 100,000 takes days, not hours, and each job shows its estimated finish time. |
| Catch-all handling | Catch-all (accept-all) addresses stay risky, never valid, and are graded higher, medium or lower likelihood with the reasons. Anything a mail server does not confirm is risky. |
| API and MCP | REST API on Pro, Business and Agency (Pro includes 10,000 calls a month, then $1.50 per 1,000). Remote MCP server with 6 tools for Claude, ChatGPT, Cursor and VS Code. No API on Starter or Growth. |
| Integrations | Connects to Instantly, Smartlead, HubSpot and Mailchimp by API key: verifies a campaign or list and tags each contact with its result. CSV in and out for any other tool. |
| Phone | Free phone format checks (country, type range). Live carrier and line-type lookups are a $20/mo add-on (5,000 a month). It never says a number is in service. |
| What it does not do | No sending, warmup or inbox placement tests. No published accuracy benchmark against other verifiers. Catch-all domains, Yahoo and AOL cannot be confirmed, and Outlook.com and Hotmail mailboxes are not probed while Microsoft refuses checks from our server's network: all of these come back risky, never valid. |
SimpleVerifier facts from our pricing page and product. Last updated .
Test it on a real address first
Type any address. It gets the same check the paid plans run: syntax, the domain’s mail servers and, where the provider allows it, a live mailbox check. Nothing is sent to the address.
Five checks a minute, no account needed. Nothing is sent to the address — we ask its mail server whether the mailbox exists, then disconnect.
Have a list? Sign in with Google and the first 100 addresses are checked free, with results to download. No card.
By continuing you agree to our Terms and Privacy Policy.
What each answer means
Valid: the mail server accepted the mailbox and the domain is not catch-all. Invalid: the server said the mailbox does not exist, the domain cannot receive mail, or the domain is a known disposable one. Risky: the server would not confirm either way, for example a catch-all domain, a provider that accepts every address or a server that timed out. Each result carries a reason, so you can see which.
When nobody can tell you
Gmail and Google Workspace answer mailbox checks clearly, and iCloud rejects unknown users. Yahoo and AOL accept every address during the check, catch-all company domains accept everything, and Microsoft is currently refusing checks from our server's network, so SimpleVerifier does not probe Outlook.com, Hotmail or Live mailboxes right now. All of those come back risky, never valid. Our mailbox provider study records how 51 providers answered.
Checking a whole list
Upload a CSV (up to 100,000 rows a file) and every row gets the same check. Mailbox checks are paced, because mail servers slow down or block verifiers that probe too fast, and the daily check capacity is shared between customers. Addresses that need no mailbox check, such as broken syntax, dead domains and disposable addresses, come back at once. The rest run in a queue, and the job card shows an estimated finish time.
When another tool is the better pick
- You need to know the person reads the inbox. No verifier can tell you that; only a reply or a click can.
- You are checking mostly Outlook.com or Hotmail addresses today: we return them risky while Microsoft refuses our checks.
Common questions
- Is this email valid?
- Paste it into the free email checker. Valid means the mail server accepted the mailbox and the domain is not catch-all; risky means the server would not confirm it; invalid means the server rejected it, the domain can't receive mail, or it is a disposable address.
- Does the person know I checked their address?
- No message is sent. The check connects to the mail server, asks about the mailbox at RCPT TO and disconnects before any message is sent.
- Can I check a Gmail address?
- Yes. Gmail and Google Workspace answer mailbox checks clearly, so a Gmail address that does not exist comes back invalid.
- Why is an address risky instead of valid?
- Because the server would not confirm it: a catch-all domain, a provider that accepts every address (Yahoo, AOL), a timeout, or for now a Microsoft consumer mailbox. The reason is shown on each result.
- How many addresses can I check free?
- One at a time on the free checker with no account (five a minute), and the first 100 list checks with a Google sign-in, once per account.
Check a whole list
Pro is $39 a month and never cuts you off: the first 100,000 emails a month run at full speed, then big lists run slower. CSV uploads, the API (10,000 calls a month, then $1.50 per 1,000), the Google Sheets add-on and the email finder are included, and you can cancel any time. For smaller volumes, Starter is $9 a month for 2,500 emails a month and Growth $19 a month for 10,000 emails a month.
The first 100 email checks are free with a Google sign-in, no card, on the same engine the paid plans use.