Skip to content

Email Verify

v1.0.0

Check whether an email address can actually receive mail — syntax, MX records, disposable providers, role accounts and likely typos.

2 endpoints
Price per call
$0.003
Free each month
100 calls
Rate limit
120/min
MCP server
Included

Overview

Email Verify tells you whether an address is worth sending to, and why.

Each address goes through four independent checks. Syntax rejects addresses no mail provider would accept. DNS resolves the domain's MX records — the one signal that proves a domain can receive mail at all, and the check that catches dead and mistyped domains. Disposable detection flags throwaway providers. Role-account detection flags addresses like info@ or support@ that reach a function rather than a person.

The response is a verdict of deliverable, risky or undeliverable, a confidence score, and a plain list of the reasons behind it — so you set policy yourself rather than accepting a single opaque number.

Common domain typos are recognised: user@gmial.com returns a didYouMean of user@gmail.com, which recovers signups that would otherwise be lost silently.

There is no SMTP probe. Connecting to a mail server to test an address is unreliable — most large providers accept everything and discard later — and the practice gets the probing address blocklisted, which degrades results for everyone.

Make your first call

Every request goes through the Twotic gateway, which authenticates your key, applies the rate limit, meters the call and forwards it. The exact amount charged comes back on the X-Twotic-Cost header.

curl -X GET "https://www.twotic.dev/v1/email-verify/verify" \
  -H "Authorization: Bearer $TWOTIC_KEY"

Endpoints

What you can build

Validate at signup, before the welcome email

Call verify when the form is submitted. An undeliverable verdict lets you show the error while the user is still on the page, and a typo suggestion recovers the signup outright instead of losing it to a bounce nobody sees.

Clean a list before a campaign

Run an existing list through the batch endpoint and suppress everything undeliverable. Bounce rate is what mailbox providers use to decide whether your future mail reaches the inbox, so this protects every send after it.

Block throwaway addresses on free tiers

Disposable providers are how one person becomes a thousand free accounts. Flagging them at signup is considerably cheaper than detecting the abuse afterwards.

Use Email Verify from an AI agent

Every endpoint above is also an MCP tool. Pick your client and the steps below fill in with this API’s real server URL, so there is nothing to substitute.

In claude.ai and the Claude desktop app

  1. 1Open Settings, then Connectors.
  2. 2Choose Add custom connector.
  3. 3Paste the server URL below and confirm.
  4. 4A Twotic sign-in page opens. Approve the connection.
  5. 5Start a new conversation. The tools are available there.

Server URL

https://www.twotic.dev/api/mcp/email-verify

Signs you in through Twotic. Access expires hourly and renews itself, and you can revoke this one app without touching your API keys.

Once connected, the tools are named email-verify_<endpoint>. Every Email Verify endpoint becomes one. Calls are metered exactly like an HTTP request, against the same allowance and balance.

Frequently asked

Does it connect to the mail server to check the mailbox?+

No. SMTP probing is unreliable and harmful: major providers accept-then-discard, so a probe proves nothing, and the traffic gets the probing address blocklisted. The checks here are DNS and heuristic, which is what actually correlates with deliverability at scale.

What does the score mean?+

A 0-100 confidence that mail will be delivered and read by a person. Above 90 is a clean individual mailbox on a domain that accepts mail; around 55 is a role account; around 20 is disposable; below 10 means the domain cannot receive mail at all.

How accurate is disposable detection?+

It is tuned to catch the providers behind the overwhelming majority of throwaway signups without the false positives that huge stale lists produce. A wrongly rejected real customer costs far more than a missed throwaway.

Can I verify a whole list at once?+

Yes. The batch endpoint takes up to 100 addresses per call and checks them concurrently, returning per-address results plus a summary. It is priced at $0.15 per batch — half the per-address rate.

Are the addresses I submit stored?+

No. Addresses are checked in memory and discarded when the response is written. Nothing is retained and nothing is added to any list.