FrozenSpam
FR Start for €1

Zero spam.
Zero false positives.

FrozenSpam is the anti-spam you install once, which never lets a spam through again — without ever blocking a real email.

Start for €1 See how it works

Fully refundable within 15 days · No commitment

★★★★★ In production since 2014 — close to one million spams blocked across all mailboxes. Zero documented false positive in twelve years.

Battle-tested for 12 years on:

ACMEHORUSSCI Le 3 rue DésiratUrban Food District

How is this possible.

Three visible principles. Five filtering layers behind the scenes (DNSBL → SPF/DKIM/DMARC → antivirus → backscatter guard → challenge-response). Technical details →

Your real contacts always get through

You open your inbox every morning without fearing a false positive. If someone is already in your contacts, their email arrives directly. No challenge, no wait.

Strangers prove they're human

A sender you don't know receives an automatic challenge: a simple email to validate. If they're human, they validate in 10 seconds and their email arrives. If they're a bot, they don't validate.

Your outbound becomes contacts

If you write to someone, their reply never triggers a challenge. It's the guarantee that no conversation you started will be blocked. Nobody else does this.

What no one else does.

Honest comparison with the solutions you've already considered.

FrozenSpamMailInBlackSaneBoxGmail
Auto-whitelist outbound✓✘≈✓¹
Backscatter guard SPF/DMARC✓✘✘✓
Public pricing✓✘ quote✓✓
France hosting✓✓✘ US✘
Content not read✓≈✓ headers✘
No commitment✓✘ annual≈✓
Identified author✓✘✘✘

¹ Gmail does this internally on its own messaging, but doesn't expose it to your professional mail server.

One price. Published. No quote required.

Monthly. Cancel in two clicks. No commitment. It's in our terms.

Solo
€4.90 excl. VAT / month

1 mailbox · 1 domain

For the independent who wants peace.

Start for €1
Most chosen
Team
€3.90 excl. VAT / box / month

2 to 10 boxes · unlimited domains

For the small business that wants a calm inbox.

Start for €1
SMB
€2.90 excl. VAT / box / month

11 to 50 boxes · enhanced SLA

For the SMB tired of false alerts.

Start for €1

More than 50 boxes? Volume pricing down to €1.50/box/month. Request a volume quote

« I wrote the first version of FrozenSpam in 2014, in Visual DialogScript, hooked into SmarterMail. It still runs. Close to a million spams blocked across all my domains. Zero false positive. Now I'm porting it as a Python SaaS to make it available. »
Emmanuel Daunizeau
Emmanuel DaunizeauCreator of FrozenSpam · Founder of V-Softs

The real questions.

No. SPF, DKIM, DMARC verify that a sender has the right to send — not that they have something legitimate to say. Spammers buy domains and configure SPF perfectly. FrozenSpam combines both: authentication first, challenge second. And it works.
Once. On their first email. And only if they aren't already in your contacts or if you haven't written to them before. Over 12 years of production, the rate of unchallenged real humans is under 1%.
Two MX servers in parallel on distinct IPs. If one falls, the other takes over. If both fall, your MTA retries for 24 hours per RFC 5321. No email is lost.
The content of your emails is never analyzed by default. The decision is made on headers, SPF/DMARC result, and your contact lists. Original mail is only stored during quarantine (30 days max) then purged.
Yes. Your whitelists and reply template are exportable as JSON anytime from the dashboard. If you cancel, your data is purged 30 days later and your MX can be repointed in 5 minutes.

See all questions

Your inbox becomes calm again in five minutes.

You repoint your MX. You forget. First month at €1, fully refundable within 15 days if you're not convinced. No commitment.

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