Run a free deliverability check on any email domain. BounceZero tests SPF, DKIM, DMARC, blacklist status, and domain reputation to identify exactly why your emails aren't landing in the inbox.
Backed by & listed on
BounceZero checks these signals for every email it verifies, giving you a complete picture of deliverability risk per recipient domain.
Sender Policy Framework defines which mail servers are authorized to send email for a domain. Missing or misconfigured SPF causes emails to fail authentication and land in spam — or get rejected outright.
DomainKeys Identified Mail adds a cryptographic signature to emails. Without DKIM, receiving servers can't verify the email wasn't tampered with in transit — reducing deliverability significantly.
Domain-based Message Authentication, Reporting, and Conformance. DMARC ties SPF and DKIM together and tells receiving servers what to do with unauthenticated email. Critical for domain protection and inbox placement.
Checks whether the sending domain or IP appears on major DNS-based blacklists (DNSBLs). A single blacklist listing can cause email to be blocked across millions of mailboxes simultaneously.
Domain age, registration history, and behavioral signals affect how ISPs perceive your sending domain. New domains, recently transferred domains, or domains with complaint history face tighter scrutiny.
BounceZero also checks BIMI (brand indicators for message identification), MTA-STS (strict transport security), DANE, and Certificate Transparency — signals that forward-looking ESPs use to score sender trust.
Teams that run deliverability checks before campaigns consistently see better inbox placement.
Block 800+ throwaway email providers at sign-up with real-time detection.
Identify domains that accept all email — including non-existent mailboxes.
Detect pristine, recycled, and typo-based spam traps before you send.
Run a live SMTP handshake to verify a single email address in real time.
BounceZero checks SPF, DKIM, DMARC, blacklists, and reputation for every email you verify. 100 free checks every month.
Start FreeAlso check our SMTP checker tool for live SMTP connection testing.
Follow BounceZero