Spaw vs Bouncer
Bouncer is an email verification service with pay-as-you-go credits that never expire, high-throughput batch APIs, a real-time form product (Bouncer Shield) and a Deliverability Kit subscription.
The table uses Bouncer's public pricing and documentation pages as checked on 2026-09-13, and Spaw's own pricing page. A row those pages carry no value for is marked "not on the pages read" rather than guessed at, and that is a statement about the reading and not about what Bouncer publishes.
| spaw | bouncer | |
|---|---|---|
| Pricing model | Pay-as-you-go credit packs whose credits never expire, or optional plans, billed monthly or yearly, that deposit the same credits every month for less and roll unused plan credits over up to three months' allowance; both through Stripe Checkout | Pay-as-you-go credits that never expire (from 1,000 credits for $8 up to 1,000,000 for $2,000), auto-refill, plus a Deliverability Kit subscription at $25 to $250 a month |
| Free tier | 100 free credits every month, no card required | 100 free credits, no card required |
| Price per 1,000 at about 10k | $7.80 (Growth pack: 5,000 credits for $39), or $5.80 on the Growth monthly plan (5,000 credits for $29 a month) | $6.00 (10,000 credits for $60) |
| Price per 1,000 at about 100k | $4.49 (Volume pack: 100,000 credits for $449), or $3.49 on the Volume monthly plan (100,000 credits for $349 a month) | $4.00 (100,000 credits for $400) |
| Unknown or catch-all results billed | No: an unconfirmed mailbox (reason unverified) and an answer Spaw could not obtain because its handshake partner was unavailable are free and leave no 7-day repeat marker, so a later lookup is a fresh one; a catch-all answer costs 1 credit like any risky answer, and an automatic re-check bills 1 credit only when it confirms the mailbox | No |
| Undeliverable results billed | No, within a fair use: undeliverable answers that needed a mailbox probe are free up to max(500, your billed email answers) in a rolling 30 days, then 1 credit each; the rest are always free | Yes |
| SMTP mailbox check | Yes | not on the pages read |
| Catch-all handling | A catch-all answer is remembered per domain for 7 days, and every unconfirmed mailbox carries a published 0 to 100 mailbox_confidence estimate | Returns an acceptAll domain property; unknown results and duplicates within a list are never charged |
| Bulk limit | 100,000 addresses per bulk job, with an HMAC-signed completion webhook | Up to 100,000 emails per batch (1,000 to 10,000 recommended); up to 60 batches a minute and 200 requests a minute to the other batch endpoints |
| Batch API | 50 addresses per synchronous request, probes sent concurrently | Synchronous batch of up to 10,000 emails at 100 requests a minute; asynchronous batches as above |
| Rate limit | 5 requests per second per key on the email and consistency endpoints | Real-time API: 1,000 requests a minute by default |
| Official SDKs | Python, Node.js, PHP | Java |
| Data retention | Only email verification keeps a history row, for 30 days, then pruned; test addresses are never logged | Results are kept for 24 hours so an address is not verified twice in that time; after that it is verified and charged again. A broader retention policy is not stated on the pages checked |
checked 2026-09-13 · sources: Bouncer pricing, Bouncer batch API, Bouncer batch sync API, Bouncer real-time API, Bouncer integration guidelines
When Bouncer fits better
Teams that want the lowest published per-check price with high batch throughput and a real-time form product.
- Bouncer Shield protects forms in real time
- Toxicity list checks
- Auto-refill and volume discounts
When Spaw fits better
Developers who want one flat price per answered lookup across every signal a signup form produces, a transparent risk score, and an API that documents every field.
- Bouncer's published rates are $6.00 per 1,000 at 10,000 credits and $4.00 at 100,000; Spaw's packs are $7.80 and $4.49, and its monthly plans $5.80 and $3.49
- Both leave unknown results unbilled; Spaw also leaves undeliverable verdicts free within a fair-use allowance
- Spaw's rate limit is 5 requests a second, 300 a minute; Bouncer's real-time API allows 1,000 a minute
- Spaw ships Python, Node.js and PHP clients plus an MCP server; Bouncer ships a Java client
Questions
Does Spaw charge for catch-all or unknown results?
Spaw bills per answer, not per probe outcome. A catch-all domain comes back risky with reason catch_all and costs 1 credit like any risky answer. A mailbox the handshake could not confirm (greylisting, a timeout, no definite answer) comes back risky with reason unverified and is free, and so is an answer Spaw could not obtain at all because its handshake partner was unavailable; neither leaves a 7-day repeat marker, so a later lookup is a fresh one (an uncertain result is reused for up to 15 minutes, then the mailbox is asked again) and bills 1 credit only once the mailbox is confirmed, and the automatic re-checks behind callback_url bill 1 credit only when they confirm it. Undeliverable verdicts are free within a fair use of max(500, your billed email answers) in a rolling 30 days, and invalid input and repeats within 7 days are free too. Bouncer states that it does not bill unknown results.
Can I move a list from Bouncer to Spaw?
Yes. Upload the CSV to the dashboard or POST it to the bulk endpoint; Spaw keeps your columns, adds the verdict columns, and lets you download only the deliverable, risky or undeliverable rows. Addresses that come back undeliverable join your suppression list so later runs skip them for free.
Is there a free tier?
Every Spaw account receives 100 free credits at the start of each month with no card on file, and unused free credits accumulate. Bouncer offers: 100 free credits, no card required.
Try Spaw on your own list
Free credits every month, no card. Upload a list, keep your columns, and download only the rows you want. See the pricing page for every rule, or the Bouncer alternatives.
Bouncer is a trademark of its owner. Spaw is not affiliated with it. Markdown version: /compare/bouncer.md