What it does
ZeroBounce checks email addresses in bulk or through an API, returning detailed classifications for valid, invalid, catch-all and uncertain results. Business or premium-domain signups receive 100 free verifications each month. Larger jobs use purchased credits or a ZeroBounce ONE subscription.
Keep the sub-status when exporting a ZeroBounce result. Its documentation distinguishes a catch-all address, whose individual mailbox cannot be confirmed, from a valid result carrying accept_all because the domain is on the vendor's vetted list. An alias can also be valid while forwarding to a different inbox. Keeping both fields lets you tell a confirmed address from one that needs further review.
For an existing newsletter list, inspect the separate classifications before deciding how each group moves back into the sending system. Unknown results and duplicates are not charged. The recurring free option offers 100 monthly validation credits for eligible business or premium-domain signups. Pay-as-you-go purchases start at USD 39 for 2,000 validations, while ZeroBounce ONE starts at USD 99 per month. Credits remain valid during an active ONE subscription. Outside it, expiry depends on when the account or credits were created and the applicable purchase or promotional terms.
Strengths
- Sub-status fields explain important differences inside the main classification
- Unknown results and duplicate removal do not consume paid validation credits
Watch out for
- Catch-all results do not confirm that the individual mailbox exists
- Credit expiry outside an active subscription depends on applicable account and purchase terms
Best for
- Email operations teams preserving detailed result classifications during list maintenance
Sources
- Email Validation Tools & Email List Cleaning | ZeroBounce (Oct 25, 2026)
- API Status Codes Documentation | ZeroBounce (Oct 25, 2026)
- Email Validation Pricing | ZeroBounce (Oct 27, 2026)