Free Email Verification API — no signup, in-browser (SignupDoggy)

Free email verification API: instantly detect disposable, throwaway, and fake email addresses in your browser. No signup, no API key, no tracking. 200,000+ domain blocklist. Same data that powers the paid SignupDoggy API. Honest comparison with AbstractAPI, Mailcheck, Verifalia, Hunter.io, ZeroBounce.

Looking for a free email validation API that actually ships? This page covers what "email validation" really means, what the free options are in 2026, and why SignupDoggy's free disposable email checker is the best starting point for indie SaaS teams.

## What "email validation" actually means

Email validation can mean syntax, MX, SMTP probing, role-based, disposable, free-provider, typo suggestion, or catch-all detection. Different APIs do different subsets.

## What the free options are in 2026

Free email validation APIs ranked:

- **SignupDoggy** — unlimited free in-browser disposable check at /disposable-checker, no signup
- **AbstractAPI** — 100/month then paid
- **Mailcheck.ai** — 200/month
- **Verifalia** — 25 one-shot credits
- **Hunter.io** — 50/month
- **ZeroBounce** — 100 one-shot credits

## Why SignupDoggy's free tier is different

Most "free tier" APIs give you N requests per month (25 to 200). After that, you pay. SignupDoggy gives you **unlimited free in-browser disposable email checks** at /disposable-checker (no signup) plus 5,000 free API calls if you sign up for the Solo pack ($5).

## When to use the in-browser checker vs the paid API

Use /disposable-checker (free, in-browser) when you need disposable email detection at signup with zero latency overhead. Use the paid API when you also need IP risk scoring (Tor/VPN) or phone number validation. Most production SaaS uses both.

## What about SMTP probing?

We deliberately don't do SMTP probing. It's slow (100ms–2s), risks IP blacklisting by major ESPs, and is unreliable against catch-all domains. For disposable email + role-based + free provider detection, you have the blocklist. You don't need SMTP.

## Get started

Try the free disposable email checker at /disposable-checker — no signup, no API key, no tracking. Buy credits at /pricing if you outgrow it.