← All posts · 2026-06-18

Why MailGuard: A Cheaper Email Verification API for Developers

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Most email verification APIs are priced like enterprise software for what is, under the hood, a regex, a DNS lookup, and a couple of lookups against a list. MailGuard exists to do the same job for a fraction of the price, with a developer experience that takes minutes, not meetings.

What it does

One HTTP call (or one line with the SDK) returns:

Syntax validation
MX / domain checks (can the domain actually receive mail?)
Disposable / throwaway detection
Role-account flags (info@, admin@)
"Did you mean gmail.com?" typo suggestions
A 0–100 deliverability score you can threshold on

It's a fast syntax + MX + heuristic verifier, which is exactly the right level for stopping bad emails at signup.

Why it's cheaper

MailGuard runs entirely on Cloudflare Workers with no database (MX results are cached in KV). Hosting costs are effectively nothing, and it scales to zero when idle. Because the marginal cost per check is tiny, the pricing can be up to 100× cheaper than the next cheapest incumbents and still be sustainable. There's no enterprise markup baked in.

Built for developers

Free tier: 500 verifications a month, no card required.
One call: plain REST, works with any stack.
Official SDK: npm install mailguard, zero dependencies, fully typed.
Privacy-first: the addresses you verify aren't stored (only the domain's mail-server result is cached), which keeps it clean for UK/EU GDPR.

Try it in 30 seconds

Paste any address into the free email checker, no signup needed. When you're ready to wire it into your app, grab a free key and drop it into your signup flow.

Try MailGuard free — 500 verifications a month, no card required. Get a key →