Free outside-in scan
Scan your site
like a monitor would
Twelve outside-in checks — uptime, TLS, DNS, redirects, domain expiry, security headers, exposed files, SPF, DMARC, HSTS, MX and CAA — the same kind of outside-in signals Holter can keep watching in production. No account, no agent, no access to your systems.
- 12 outside-in checks, run live while you watch
- Full report to your inbox — every finding explained
- No account, no agent, no access to your systems
We emailed a 6-digit code to . Enter it to start the scan — it expires in 10 minutes.
What the scan looks at
The same outside-in signals a monitor watches in production — checked once, from outside your infrastructure.
Uptime
Does the site answer from outside your own network — and how fast?
TLS certificate
Valid, trusted, and not quietly about to expire.
DNS
Records resolve, and resolve consistently.
HTTP → HTTPS
Plain-http visitors land on the secure site.
Domain expiry
The registration isn't running out on you.
Security headers
CSP, content-type protection, frame and referrer policies.
Exposed files
.env, .git and friends return 404 — never 200.
SPF
Receiving servers can trust your outbound mail.
DMARC
Nobody can spoof mail from your domain.
HSTS
Browsers stay pinned to HTTPS.
MX records
Inbound mail routing actually works.
CAA
Only your chosen authority may issue your certificates.
How it works
Enter your URL and email
We email you a 6-digit code — it keeps bots from draining the free pool, and it's where your report lands.
Watch the checks run live
Twelve outside-in checks, streamed as they complete — most scans finish inside a minute.
Fix what gets flagged
The full report lands in your inbox with every finding explained in plain language.
What a scan can't see
A scan is a snapshot of your front door. The failures that hurt most are silent and inside: the queue worker that dies on a Friday, the backup cron that went quiet three weeks ago, the email provider bouncing while your API keeps answering 200. Monitoring watches both directions — outside-in checks on a schedule, plus dead-man heartbeats for the things no scan can reach.
Turn the snapshot into a watchman
Every check above can become a monitor that runs on a schedule and tells you the moment something drifts. Free plan: 5 monitors, 5-minute checks, no credit card.