The 8 Best Email Verification APIs in 2026
An email verification API lets your own code check addresses before you send. These are the eight we would shortlist, compared on how you call them, what 10,000 addresses cost and what you get free.
Updated 5 November 2026
Emailchaser is our pick if you verify whole lists from code. You create a job with up to 50,000 addresses, read its progress and download the results, and every address is checked by two separate services for $1.70 to $3.40 per 1,000 on top of a plan from $47 a month.
If you send from Emailchaser too, the list is verified and sent from the same account.
Here is how the eight email verification APIs compare at a glance.
Swipe sideways to see every column.
| # | Tool | Entry price | 10,000 addresses | Free start | What its page says about the API |
|---|---|---|---|---|---|
| 1 |  Emailchaser | $1.70 per 1,000 at the least, on a plan from $47 a month | $17 to $34 | 7-day trial, 100 addresses from a list | Job-based: up to 50,000 addresses a job, results as CSV or records |
| 2 |  ZeroBounce | 2,000 credits for $39 | $129 | 100 free credits a month | One credit per address, bulk or real-time |
| 3 | Kickbox | 1,000 for $10 | $70 | 100 free | Unknown results are free |
| 4 |  Emailable | 5,000 credits for $38 | $60 | 250 free credits | Credits never expire |
| 5 | Bouncer | 1,000 credits for $8 | $60 | A free start, no card | Credits never expire |
| 6 | Abstract API | Starter, $19 a month for 5,000 requests | See their site | 100 requests a month | One JSON response per check |
| 7 | Clearout | 5,000 credits for $40 | $65 | 100 credits, no card | Free plan limited to 3 requests a minute |
| 8 | EmailListVerify | 1,000 credits for $5 | $27 | See their site | Credits do not expire |
Prices as published on each vendor's own pages, pay-as-you-go where a vendor sells it, read on 5 November 2026. Each card below links to the vendor's page.
Verifying 10,000 addresses costs $17 to $34 with Emailchaser, against $27 to $129 for the packs the others print.
Emailchaser bills $0.0017 a check and an address takes 1 or 2, so the bar runs from $17 to $34, and it is billed on top of a plan from $47 a month. The others are each vendor's pay-as-you-go price for a 10,000-credit pack. Abstract API is sold by the request and is not in the chart. Read 5 November 2026.
Email verification APIs come in three shapes, and the shape decides where in your product you can call them.
Abstract API answers one address per request, and ZeroBounce's real-time API does too, which suits a signup or checkout form.
Emailchaser's API takes a list, runs it as a job and hands back the results, which suits imports, CRM exports and scheduled clean-ups.
Kickbox, Emailable, Bouncer, Clearout and EmailListVerify sell pay-as-you-go packs, so the price is per address and nothing renews.
Emailchaser's API covers the rest of outbound too, so a verified list can go straight into a campaign.
Verify a list from your own code and send to it in five steps.
- Make a keyCreate an API key with read and write access in your Emailchaser account.
- Start a jobPost your list of addresses to the create-job endpoint.
- Watch itGet the job to read its progress and what it has billed.
- DownloadFetch the results as a CSV or as a list of records.
- SendAdd the clean addresses to a campaign with the leads endpoint.
For one address by hand, the free email checker shows what a verified result looks like.
We compared them on five things that decide which API fits a developer.
- How you call it: per address, per list or per job.
- What 10,000 addresses cost, where the vendor prints a pack that size.
- What you get free before you pay.
- Whether credits expire.
- Whether the verified list can go into the account that sends the campaign.
Every fact below comes from the vendor's own pages, read on 5 November 2026.
These are the eight email verification APIs worth a look in 2026.
1. Emailchaser's verification API checks a list of up to 50,000 addresses as one job, for $1.70 to $3.40 per 1,000 addresses.
You post a list of addresses to the API, it runs the list as a verification job, and you read the progress and download the results as a CSV or as records. Each address is checked by two separate verification services, so the answer is not one vendor's opinion.
- Billing is $0.0017 a check: one check when the first service rejects an address outright, two otherwise, so $1.70 to $3.40 per 1,000 addresses on top of a plan from $47 a month.
- The API has seven verification endpoints: list jobs, create a job, get a job, cancel a job, download a job as CSV, list a job's records and read the verification rate.
- Listing and reading jobs works with a read-only key, and starting a job needs a key with read and write access.
- A free trial verifies up to 100 addresses from a list.
Best for: Developers who clean an import, a CRM export or a purchased list in code, then send it from the same account.
2. ZeroBounce sells 2,000 credits for $39 and 10,000 for $129, with the same credit for bulk and real-time checks.
ZeroBounce's pricing page says every plan uses one credit per email address verified, whether you use bulk validation or the real-time API.
- The pay-as-you-go packs run from 2,000 credits at $39 to 10,000 at $129.
- A monthly subscription, ZeroBounce ONE, starts from $99 a month.
- The free plan gives 100 credits a month.
Best for: Teams that want one credit to cover both a list clean-up and a signup-form check.
Source: zerobounce.net/pricing, read 5 November 2026.
3. Kickbox sells 1,000 verifications for $10 and 10,000 for $70, and its pricing page says unknown results are free.
Kickbox sells pay-as-you-go verification packs and lists its Email Verification API on the same page. Its pricing page includes a section headed Unknown Verification Results Are Free.
- Packs go from 1,000 verifications at $10 to 10,000 at $70 and 100,000 at $500.
- A free start of 100 verifications is listed on the page.
Best for: Teams that verify in moderate batches and want unknown results off the bill.
Source: kickbox.com/pricing, read 5 November 2026.
4. Emailable sells 5,000 credits for $38 and 10,000 for $60, and its credits never expire.
Emailable's pricing page sells pay-as-you-go credit packs with a slider for the size and lists a free start of 250 credits.
- 5,000 credits cost $38 and 10,000 cost $60 on the page.
- Its pay-as-you-go credits never expire.
- 250 free credits come with a free account.
Best for: Teams that verify in bursts and do not want to use credits up by a date.
Source: emailable.com/pricing, read 5 November 2026.
5. Bouncer sells 1,000 credits for $8, 10,000 for $60 and 100,000 for $400, and its credits never expire.
Bouncer's pricing page sells email verification credits on demand and says purchased credits never expire. Its smallest pack is 1,000 credits.
- The page says you can start for free without a credit card.
- At 100,000 credits the pack works out to $4 per 1,000.
Best for: Teams that clean a list now and then and want a small first purchase.
Source: usebouncer.com/pricing, read 5 November 2026.
6. Abstract API's Starter plan is $19 a month for 5,000 requests, and each check returns in one JSON response.
Abstract API is sold by request, not by list. Its page says every check returns in one JSON response, with syntax, MX record, SMTP deliverability, disposable domain and catch-all checks in the same request.
- The free plan is 100 requests a month, with no credit card.
- Starter is $19 a month on monthly billing for 5,000 requests, and Standard is $35 and Professional is $39.
- Yearly billing lowers the monthly price.
Best for: Developers who validate an address inside a signup form and pay by the request.
Source: abstractapi.com, read 5 November 2026.
7. Clearout sells 5,000 credits for $40 and 10,000 for $65, and its free plan includes the verification API at 3 requests a minute.
Clearout's pricing page lists a free plan with 100 credits and no credit card, and rate limits for its Email Verification API on each plan.
- The free plan's API is limited to 3 requests a minute, and the Starter plan's to 25.
- Pay-as-you-go packs run from 5,000 credits at $40 to 10,000 at $65.
Best for: Developers who want to try an API for free before buying credits.
Source: clearout.io/pricing, read 5 November 2026.
8. EmailListVerify sells 1,000 credits for $5 and 10,000 for $27, and says it provides an API.
EmailListVerify's pricing page lets you type any number of credits, with a minimum of 1,000, and says one credit checks one address. Its FAQ answers Do you provide an API? with yes.
- Its pay-as-you-go credits do not expire.
- The same 10,000 credits on a monthly plan are $25 a month, 7% less.
- Credits can also be split with its email finder.
Best for: Teams that want the smallest per-address price on a public page.
Source: emaillistverify.com/pricing, read 5 November 2026.
The right email verification API depends on whether you check one address or a whole list.
| Your job | Start with |
|---|---|
| Verify a list or an import in code, then send to it | Emailchaser |
| Check one address as a visitor types it | Abstract API or ZeroBounce |
| Buy a pack of credits that never expire | Emailable, Bouncer or EmailListVerify |
| Pay nothing for unknown results | Kickbox |
| Try an API free before buying | Clearout, Abstract API or Emailchaser's trial |
Related reading: the best email verification tools, the best bulk email verification services, the best email list cleaning services and the best email deliverability tools. To check an address now, use the free email checker, and to see the rest of the API, read about the cold email API. For every kind of tool, see the best cold email and sales tools.
People ask these questions about email verification APIs.
What is the best email verification API in 2026?
For developers who clean whole lists in code and then send them, we pick Emailchaser: one job checks up to 50,000 addresses with two separate services at $1.70 to $3.40 per 1,000, and the results sit beside the campaign. For a signup form that checks one address, Abstract API and ZeroBounce answer per request.
Can I verify a whole list with one API call?
Yes. With Emailchaser you post a list of up to 50,000 addresses as one job, read its progress and download the results as a CSV or as records.
How much does email verification cost per 1,000 addresses?
From the vendors' own pages, a 10,000-credit pack costs $27 at EmailListVerify, $60 at Emailable and Bouncer, $65 at Clearout, $70 at Kickbox and $129 at ZeroBounce. Emailchaser bills $1.70 to $3.40 per 1,000 addresses on top of a plan from $47 a month.
How many addresses can I verify in one request?
With Emailchaser, one job takes up to 50,000 addresses on a paid plan, and a free trial takes up to 100 addresses from a list. Per-request APIs such as Abstract API check one address per request.
Can I try an email verification API for free?
Yes. Clearout gives 100 credits, Kickbox 100, ZeroBounce 100 a month, Emailable 250 and Abstract API 100 requests a month. Emailchaser's 7-day free trial verifies up to 100 addresses from a list, and its free email checker verifies one address at a time on the website.
What key does Emailchaser's verification API need?
Listing and reading verification jobs works with a read-only key. Starting a job spends money, so it needs a key with read and write access.
Do email verification credits expire?
On their own pages Emailable, Bouncer and EmailListVerify say their pay-as-you-go credits do not expire. Check each vendor's page for subscription credits, which can work differently.
Still not convinced?
Read all 34 customer messages.
SEE REVIEWSP.s. these are actually real reviews (not fake G2 reviews) 🙂
“Btw thanks for your continuous help, best support ever! It means a lot as when I understand how the tool works, esp. In problematic situations, and And what it can do and cannot so from the start, I have more trust. There’s nothing worse for a user than what Smartlead does: lots of great features that don’t really work, including crucial ones for a sequencer like auto fallback to connected accounts when account gets disconnected (doesn’t have to get back to the original one after reconnection, no one expects miracles, just a solid infra delivering on its specs - not promises), plus their low quality support when the issues are revealed.”
“Got my first reply with Emailchaser :)”
“We've recently upgraded to the premium plan to increase our sending volume. Just wanted to say thanks for such an awesome platform and the support you've already given in getting us started.”
Ready to let your AI agent set it up?
Give it your website. Approve once.
Start my free trial