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CaptainDNS
100% free · no sign-up required

Paste anything DNS or email.
Get a full audit in seconds.

Domain, IP, email, URL or raw DNS record. We detect the input and run the right audit in under 3 seconds.

https://captaindns.com/audit/

Try an example: ··

1.5M+ domains audited this month · 7 protocols checked in parallel · under 3s p95

Hosted services

Continuous monitoring and policy hosting

For the parts of your stack that need uptime, alerts and a real owner, not a one-off check.

DMARC Monitoring

Real-time rua/ruf reports, sender breakdowns and alerts when alignment breaks.

Live · 4 senders detected
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Email Security Monitoring

Continuous monitoring of your email security and deliverability. Get alerted whenever a score or DNS record changes enough to affect deliverability or security.

9 protocols monitored
Learn moreNew

HTTP monitors

Multi-region uptime checks, 3-region consensus, alerts. Security score: SSL/TLS, HSTS, headers, phishing.

EUUSAPAC
Learn moreNew

Status pages

Public status pages tied to your monitors. Custom domain, incidents, subscribers, RSS. Publishable Security score.

All systems operational
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Domain redirect

Host 301/302 redirects with HTTPS and per-link analytics. No server to maintain.

acme.com/promo → acme.io · 301
Learn more
Pricing

Simple pricing, no surprises

Audit tools stay free. Pay only for continuous monitoring, per tool.

Start with 1 free tool, no credit card.

Uptime

€3 /month excl. VAT

Email deliverability

€5 /month excl. VAT

DMARC

€5 /month excl. VAT

TLS-RPT

€3 /month excl. VAT

BIMI

€3 /month excl. VAT

MTA-STS

€3 /month excl. VAT

Domain redirect

€3 /month excl. VAT

1 free tool

Discovery version

Compare all features
Most popular

Pack

29 € /month excl. VAT
  • 10 full tools
  • 2 check regions
  • Custom-domain status page
Choose the Pack

Agency

149 € /month excl. VAT
  • 100 full tools
  • White label
  • Multi-client
Discover Agency

No credit card · No commitment · Cancel anytime.

60+ Tools

60+ tools, grouped by job to be done

Pick a category. Each tool ships with a live output preview.

Blog

Latest from the blog

Deep dives on DMARC, DNSSEC, deliverability and modern email security.

Read all articles
FAQ

Frequently asked questions

Everything you wanted to know before signing up.

Is the free plan really free?

The 60+ audit tools stay free, no sign-up required. Continuous monitoring: 1 tool in discovery mode, free without a credit card. Each extra tool is billed per unit (€3 or €5/month).

Can I change my plan at any time?

Yes. Add or remove tools at any time, with no commitment. Billing is monthly and prorated by Paddle.

Do you store the domains I audit?

Audits run on the fly and are not persisted unless you save them in your account. We keep aggregate counters only, no PII, no third-party trackers.

Is billing monthly?

Yes. Everything is monthly, with no commitment: each tool costs €3 or €5 per month. Payments are handled by Paddle (card, PayPal, Apple/Google Pay).

What happens if I exceed my API credits?

Every free account gets 30 API credits per month, 50,000 with the Pack. Monitoring tools have no cap: each tool beyond the free one is billed per unit.

What payment methods do you accept?

Credit card (Visa, Mastercard, Amex), PayPal, Apple Pay and Google Pay via our billing partner Paddle. Enterprise contracts support wire transfer and SEPA.

How does DMARC reporting work?

We parse rua and ruf reports in real time, deduplicate senders, expose failures with actionable signals and alert you when alignment breaks. EU hosting, no resale.

Do you support SSO?

Yes on Agency and Enterprise. Okta, Google Workspace and Azure AD are supported out of the box; custom SAML on Enterprise.

By the numbers
Domains audited this month
1.5M+
DNS queries this month
2.3M+
Resolvers across continents
18

18 resolvers, 4 continents

API uptime · last 12 mo
99.99%