Email deliverability, with privacy built in.

What this is

EmailSheriff is a free email deliverability suite. Six tools that run the checks marketers and engineers need before hitting send: domain authentication audit (SPF / DKIM / DMARC), DNS record verification scoped to your CRM, blacklist sweeps across 12 RBLs, list verification with disposable-domain detection and typo correction, header forensics for tracing why a campaign hit spam, and spam-score testing for subject-line and body content.

None of these are new ideas. MxToolbox has done this for 20 years. DMARCian, EasyDMARC, ZeroBounce - they all run similar checks. What's different here is privacy by design: every email address you paste is hashed at the entry point of our worker. The plaintext never enters our database, never gets logged, never sits in a backup. Audits run against the hash. Domains, lists, headers - they remain on your side.

Why we built it differently

The existing tools are powerful but they were built for a different decade. ZeroBounce stores every email you upload and trains models on the aggregate behavior. NeverBounce does the same. The free tools are ad-laden and slow. The paid tools start at $20/month minimum and lock the useful features behind enterprise-only tiers.

We wanted a tool we'd actually use ourselves: fast, free for the common case, paid only when you genuinely need higher limits, and one that doesn't quietly pile up other people's customer email addresses on someone else's server.

What we're not doing

EmailSheriff isn't trying to be the deepest deliverability platform on the market. If you need reputation monitoring across hundreds of sending IPs, an SPF flattening service, or BIMI certificate management, there are better-suited products. This is for the moment when a deliverability problem actually shows up - when a marketer asks "why did this hit spam" or an engineer needs "is this list safe to send to."

The principles

• ✓Privacy is the product. Everything hashed at entry. Plaintext never touches the database.
• ✓The free tier should be useful, not crippled. Anonymous users get 500 emails per upload, full audits, all 12 RBL checks. No watermarks, no drip-fed results.
• ✓Honest comparisons. Where we're worse than competitors, the comparison page says so.
• ✓No tracking-pixel theatre. No third-party analytics until you opt in. No "we use cookies" dark patterns.
• ✓Independent. No investors, no ads, no acquisition narrative.

About this domain

EmailSheriff has been operating under new ownership since 2026. The emailsheriff.com domain was acquired from a previous, unaffiliated owner whose project ended years before this one began. Everything you see here - the tools, the privacy stance, the hashed-at-entry architecture, the principles above - is governed exclusively by the current EmailSheriff team. None of the previous use, infrastructure, or data carries forward.

What's next

Phase 1 - the six free tools - is what's live now. Phase 2 brings paid tiers (higher upload limits, SMTP-handshake verification, PDF audit reports, API access). Phase 3 brings team features (shared workspaces, audit history, Slack alerts). Phase 4 is whatever the people using it tell us they actually need.

If something's broken, slow, or wrong: tell us. This is a product we use too, and we want it to be the tool we wish existed.