A free DMARC analyzer you actually own.

Free — not a "free tier"

Most hosted DMARC tools advertise a free plan, then cap it — one or two domains, a couple of weeks of history, a low message limit — to nudge you toward a paid tier. DMARC Analyzer is free for a different reason: it's open source (Apache-2.0) and you self-host it. No domain caps, no history limits, no per-message metering.

What you get

• Unlimited domains — no tier to outgrow.
• Full report history — bounded only by your own storage.
• Multi-tenant — organise domains by client, for agencies and MSPs.
• Real dashboards — aggregate reports turned into a short to-do list, plus spoofing investigation and guided enforcement.
• Your data stays put — reports never leave your infrastructure.

How the "free" works

There's no account and no credit card — you run it yourself as a single Docker container backed by PostgreSQL. The source is on GitHub, licensed Apache-2.0, so you can read, modify, and trust it.

Is there a catch?

Not in the licence or the feature set — nothing here is held back for a paid tier, because there isn't one. The honest catch is that "free" moves from the vendor's ledger to yours: you provide the server, and you're the one who notices if a backup job fails. For most single- server setups that's a small VPS and an afternoon, not a second job — what self-hosting actually costs has the full breakdown.

How it compares to hosted "free" plans

If you want a fully managed service and don't mind cloud hosting or per-domain pricing, a hosted platform's free tier can be a fine start — see the buyer's guide. If you'd rather not send report data to a vendor or hit domain caps, compare the open-source, self-hosted options — and weigh what running it yourself actually costs, since free-as-in-licence still means you own uptime and backups.