Best free email verification APIs
A free API tier should carry you from the first test call to launch day without a card. Eight verification APIs ranked on free allowance and the step up.
How this was compared
Disclosure: ZapBounce is our product. Figures were read from each vendor's own pages in September 2026, and the criteria below were applied to every entry, ours included.
The short version
- Free test calls: whether you can run your test suite against the API without spending live credits.
- The free live allowance: how many checks, whether it renews, and whether it needs a card or a business email, as each vendor states on its own pricing page in September 2026.
- The step up: the smallest paid pack and whether it has a minimum, since a free tier is only as good as the price that follows it.
- What a paid check bills for: unknown results and duplicates, and whether credits expire.
- Disclosure: ZapBounce is our product, and the same criteria were applied to it.
At a glance
| 10,000 addresses | Credit expiry | Bills unknowns | |
|---|---|---|---|
| ZapBounce | $25 | Credits never expire | No |
| QuickEmailVerification | $60 one-time | One-time credits never expire; daily subscription credits reset and do not roll over | No |
| EmailVerify.io | $25 for 20,000 | Pay-as-you-go credits never expire; subscription credits roll two months | Not stated |
| ZeroBounce | Subscription only | Credits roll over while the subscription is active | Not stated |
| Verifalia | $49.90 at Standard quality | Purchased credits never expire; daily free credits expire each day | Not stated |
| Hunter | Plans from $49 to $299 a month | Credits expire after 12 months | No |
| Emailable | $0.0076 an address at the 5,000 entry, 15% off on a subscription | Credits never expire | No |
| Kickbox | $70 | Credits expire one year from purchase | No |
Vendor figures read from their own pricing pages in September 2026. Confirm before purchase, because prices move.
The ranking
Best first, with the situation each one fits.
ZapBounce
Disclosure: ZapBounce is our product. POST /v1/verify checks one address and returns the result, a reason, the SMTP code and flags for role, disposable and free-provider addresses, plus a did_you_mean typo hint. A zb_test_ sandbox key returns shaped results and never spends a credit, so your CI can call it on every commit.
- Best for:
- Developers wiring a signup form or a CRM sync who want free tests forever and 100 free live checks a month. Start with single verification and sandbox mode, then see the API for batches and webhooks.
QuickEmailVerification
QuickEmailVerification gives 100 free credits a day, recurring, with no card, and states plainly that it does not charge for unknowns.
- Best for:
- Low-volume projects that stay under 100 checks a day.
- Less suited to:
- Saving unused free checks, since the daily credits reset and do not roll over.
emailverify.io
emailverify.io renews 100 free checks a month and offers an MCP endpoint beside its API.
- Best for:
- Developers who want a monthly free allowance and an AI-agent connection.
- Less suited to:
- Budgeting on unknown rows, since its pricing page does not state whether unknowns are billed.
ZeroBounce
ZeroBounce renews 100 free credits a month when you sign up with a business domain.
- Best for:
- Teams who also want ZeroBounce's deliverability tools on the same account.
- Less suited to:
- Small paid top-ups, since paid credits start at a 2,000-credit minimum for $39.
Verifalia
Verifalia gives 25 free checks a day and reports why an address failed.
- Best for:
- Developers who want the failure reason on every call.
- Less suited to:
- Banking free checks, since the daily free credits expire each day at midnight GMT.
Hunter
Hunter renews 50 free credits a month, and a verification costs half a credit, beside its email finder.
- Best for:
- Projects that find and verify addresses from one API.
- Less suited to:
- Paid credits held for later, since they expire after 12 months (read 24 September 2026).
Emailable
Emailable starts new accounts with 250 free credits and refunds duplicates and unknowns.
- Best for:
- A one-time test of a larger sample before buying.
- Less suited to:
- Small paid top-ups, since purchases start at 5,000 credits.
Kickbox
Kickbox gives 100 free checks, charges only for definitive results, and adds its Sendex quality score.
- Best for:
- Developers who want a quality score in the response.
- Less suited to:
- Paid credits held for later, since they expire one year from purchase (read 24 September 2026).
Why ZapBounce ranks first
How to choose
- Daily or monthly: QuickEmailVerification gives 100 a day and Verifalia 25 a day, both resetting daily. ZapBounce renews 100 a month and adds a sandbox key that costs nothing for tests.
- Card and email: ZeroBounce's monthly free credits need a business domain. ZapBounce's 100 free checks need no card.
- After the free tier: ZeroBounce starts paid credits at 2,000 and Emailable at 5,000. ZapBounce's first paid pack is 1,000 checks for $5.
- Expiry: Hunter and Kickbox paid credits expire after a year (read 24 September 2026). ZapBounce credits never expire, and the credits endpoint shows expires_at as null.
Questions people ask
Is there a free email verification API with no credit card?
Yes. ZapBounce gives 100 live checks a month with no card, plus sandbox keys that never spend a credit. QuickEmailVerification and MillionVerifier also offer free credits without a card, read on their own sites in September 2026.
How do I test an email verification API without using credits?
Use a sandbox key. On ZapBounce, keys starting zb_test_ return shaped results without opening an SMTP connection and never touch your balance, so they are safe to run in CI.
Can I use a free email verification API in production?
Yes, for a low-traffic signup form. When signups pass 100 a month, ZapBounce's next step is 1,000 checks for $5, and unknown results are never billed.
What does a verification API return?
On ZapBounce, one of four results (valid, invalid, catch_all or unknown), a reason code, the SMTP reply, the mail host that answered, flags for role, disposable and free-provider addresses, and a typo suggestion when one fits.
Run the same sample through two of them
100 free checks a month, no card. Compare how many addresses each one declined to judge, which matters more than either accuracy claim.