ipto vs ZeroBounce
ZeroBounce is a dedicated email-verification service built around SMTP-level mailbox checks — connecting to a domain's mail server to test whether a specific address actually exists, not just whether its domain can receive mail. That's real technical depth ipto's Email Checker doesn't attempt: Cloudflare Workers can't open raw SMTP sockets, so ipto validates syntax, a live MX record, and disposable-domain status only. ZeroBounce's free tier gives 100 validation credits a month, refilling monthly and never expiring; paid plans start at $99/month for a minimum 10,000 credits.
| Feature | ipto | ZeroBounce |
|---|---|---|
| API key required | Never | Yes, for every request |
| Free tier volume | Unlimited (general free-tier budget) | 100 credits/month, refills monthly, don't expire |
| SMTP-level mailbox verification | No — Workers can't open raw SMTP sockets | Yes, connects to the domain's mail server directly |
| Catch-all domain detection & scoring | No | Yes, 1–10 AI score on likelihood of reaching a real person |
| Spam trap / abuse-email detection | No | Yes |
| Disposable-domain detection | Yes, synced CC0 blocklist | Yes |
| Live MX record check | Yes, DNS-over-HTTPS | Implicit in its SMTP-level check |
| Subscriber activity/engagement history | No (out of scope) | Yes, 30–180 day open/click history |
| Cheapest paid tier | n/a (one free tier) | $99/month minimum, 10,000 credits |
When ZeroBounce might fit better
- You need to know whether a specific mailbox actually exists, not just whether its domain accepts mail — ZeroBounce's SMTP-level check does something ipto's Email Checker structurally can't: Workers has no raw-socket access for an SMTP handshake.
- Catch-all scoring, spam-trap detection, and subscriber activity history matter for a cold-email or newsletter sending program — these are real, well-executed ZeroBounce features ipto doesn't offer.
When ipto fits better
- You want a free tier with no monthly credit ceiling — ZeroBounce's free plan caps out at 100 validations/month; ipto's Email Checker draws from the general free-tier budget instead of a separate email-specific cap.
- You don't want to register for an API key just to check a handful of addresses — ipto never requires one.
FAQ
Does ZeroBounce verify whether a mailbox actually exists?
Yes — its SMTP-level check connects to the target domain's mail server, something ipto's Email Checker can't do on Cloudflare Workers (no raw TCP/SMTP socket access). ipto checks syntax, a live MX record, and disposable-domain status instead.
How many free email validations does ZeroBounce give?
100 credits per month, refilling monthly and not expiring. ipto's Email Checker has no separate email-specific cap — it draws from the same free-tier budget as every other endpoint.
Try it: curl https://ipto.to/v1/ip/8.8.8.8 · full API reference · all alternatives