Is ZapBounce more accurate than Abstract API?

Compare coverage before accuracy. On accuracy, Abstract API's entry reads: Benchmarks available on request, per its email API page. Vendor accuracy claims in this market are calculated after unknown and catch-all addresses leave the denominator. ZapBounce reports coverage, the share of the list with a definite verdict, so the rest is visible, labeled and never billed.

Why switch from Abstract API to ZapBounce?

Credits bought per list and never expiring, so a quiet month leaves your balance where it was. One published table from $5 for 1,000 to $949 for a million, with no monthly request cap to size. Unknown results and duplicate rows are never charged, and the pricing page says so. Bulk upload for whole lists as well as the API, with your original columns returned beside each result. Our own SMTP check on port 25, closed before DATA, so no message reaches the addresses you check.

ZapBounce vs Abstract API

Abstract API bundles email validation into a family of developer APIs, each priced as a monthly request plan. ZapBounce is a verifier with pay-as-you-go credits from $5 for 1,000 and a bulk upload for whole lists. You're choosing between a request quota for your app and a price per address you check.

	ZapBounce	Abstract API
Accuracy reporting	Coverage stated: the share of your list with a definite verdict	Benchmarks available on request, per its email API page
1,000 addresses	$5	See their pricing page
10,000 addresses	$25	See their pricing page
100,000 addresses	$139	See their pricing page
Free tier	100 a month, no card	See their pricing page
Credit expiry	Never	See their pricing page
Billed for unknowns	No	Not stated

Abstract API prices change, so confirm theirs on their own pricing page. Ours are fixed and published on /pricing.

How Abstract API prices it

Abstract API lists a free monthly request allowance and three paid monthly plans, Starter, Standard and Professional, with custom Enterprise pricing and a discount for paying yearly (read September 2026). Its page doesn't say whether unused requests roll over. ZapBounce sells credits outright: $5 for 1,000, $25 for 10,000, and they never expire.

Why teams pick ZapBounce over Abstract API

What changes when your list runs through ZapBounce instead.

The short version

Credits bought per list and never expiring, so a quiet month leaves your balance where it was.
One published table from $5 for 1,000 to $949 for a million, with no monthly request cap to size.
Unknown results and duplicate rows are never charged, and the pricing page says so.
Bulk upload for whole lists as well as the API, with your original columns returned beside each result.
Our own SMTP check on port 25, closed before DATA, so no message reaches the addresses you check.

Moving off Abstract API

Abstract API sells validation as a monthly request plan sized for an app's traffic. That fits a signup form with steady volume. A marketing list arrives in bursts, though, and a monthly cap either runs out mid-file or sits unused. ZapBounce credits are bought when a list lands and they wait in your account for the next one.

If your form calls Abstract API, swap that request for POST /v1/verify with a ZapBounce key and map the result field: valid, invalid, catch_all or unknown. The role, disposable and free_provider flags come back as booleans. For lists you've already collected, upload the CSV to bulk and download it with the results added.

The hard addresses, and how they come back

Catch-alls, Yahoo, cloud blocks and traps

Abstract API flags catch-all addresses, and so does ZapBounce: one probe to a random address at the same domain, a catch_all result, one credit. What matters is the share of your list that lands there, so ZapBounce reports it beside the valid rows on every file.

Yahoo- and AOL-hosted inboxes reply 250 to every recipient to defeat enumeration. The JSON response for those signups reads unknown, the billed flag reads false, and your handler decides whether to wave the visitor through.

Burst traffic hits limits on any API. A ZapBounce 429 arrives with a Retry-After header and never costs a credit, so a busy launch day queues checks politely instead of dropping registrations.

Breach history and domain age describe an address's past. Pristine spam traps look like live mailboxes on the wire, so confirmed opt-in at signup still does that job.

Questions people ask about Abstract API

How is Abstract API's email validation priced?

Abstract API lists a free monthly request allowance plus Starter, Standard and Professional monthly plans, with custom Enterprise pricing (read September 2026). ZapBounce sells credits with no plan: $5 for 1,000 and $139 for 100,000, and they never expire.

How hard is it to swap Abstract API for ZapBounce in my code?

One request changes. Send the address to POST /v1/verify with your ZapBounce key and read the result field, which is valid, invalid, catch_all or unknown. Test it on the 100 free credits every account gets each month.

Does ZapBounce check lists as well as single addresses?

Yes. Upload a CSV, TXT or XLSX file to bulk verification and download it with your columns plus result, reason and a billed flag. Unknowns and duplicates cost nothing.

Is ZapBounce cheaper than Abstract API?

Ours is $5 for 1,000 and $139 for 100,000, published, with no minimum. Credits never expire, and unknowns and duplicates are never billed, so the rate you see is the rate you pay.

Can I test both before deciding?

Yes, and you should. Run the same sample of a few thousand addresses through each and compare how many came back unresolved. That difference matters more than either accuracy claim.

Count the validation requests your app used last quarter, then price that volume at $25 for 10,000 checks with credits that never expire.

Run the same sample through us and Abstract API

100 free checks a month, no card, and the unknowns come back labeled.

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