Continuous SSL monitoring
We poll every monitored certificate every 12 hours and detect renewal, replacement, or expiry as soon as the next check completes.
SSL Certificate Monitoring
Monitor SSL certificates before they expire.
Free SSL certificate expiry monitoring for up to 10 hostnames. SSL certificate expiry alerts by email at 30, 15, 7, 1, and on the day of expiry. Sign in with Google, Microsoft 365, GitHub, or a magic link.
Quick SSL certificate expiry date check
What it does
A focused SSL certificate expiry tracker.
Monitor SSL certificates continuously, get SSL certificate expiry reminders before the date hits, and close the most preventable outage on the public web. No agent to install, no enterprise pricing.
Smart alert windows
SSL certificate expiry alerts go out at 30, 15, 7, 1, and on the day of expiry. One email per stage, deduplicated across your team, no alert fatigue.
Bulk upload via CSV
Drop a CSV of hostnames and our SSL certificate expiry monitoring tool tracks them all in one pass, with a transparent plan-limit check before any are saved.
SSO + magic-link auth
Sign in with Google, Microsoft 365, GitHub, or a 10-minute email link. No passwords to forget.
Certificate transparency
See the issuer, SANs, signature algorithm, and chain health for every hostname you monitor.
API & webhooks
Pipe SSL certificate expiry events into Slack, PagerDuty, or your own incident platform.
About this tool
Why monitoring SSL certificate expiry is the cheapest insurance you can buy for your web presence.
Monitor SSL Certificates is a free SSL certificate expiry monitoring tool that catches renewal, replacement, and expiry failures before your customers ever see a broken padlock.
An expired TLS certificate is one of the most preventable outages in production. Every week, somewhere on the internet, a website goes dark because a sysadmin forgot to renew a cert, a Let's Encrypt cron job stopped running, or a hosting provider swapped keys without notice. The cost is immediate and asymmetric: a single expired certificate can take a checkout offline, drop search rankings overnight, and push users to your competitors in minutes. Browser warnings like NET::ERR_CERT_DATE_INVALID read as "this site is dangerous" to ordinary users, and they behave accordingly. Monitor SSL Certificates is a focused SSL certificate expiry monitoring tool built specifically to make that failure mode impossible.
What monitor SSL certificates actually does
Add any hostname and we connect on port 443, parse the full certificate chain, and store the issuer, signature algorithm, valid-from, valid-to, and subject alternative names. From that point on we poll the certificate every 12 hours on the free plan and compare it against our last-known fingerprint. If anything changes — a renewal, a CA swap, a missing intermediate, a downgrade in signature algorithm — we log the event. If the certificate is approaching its notAfter timestamp, we send you an SSL certificate expiry notification on a schedule that matches how teams actually plan renewals: 30 days, 15 days, 7 days, 1 day, and on the day of expiry. Five reminders is enough to catch a renewal; not so many that anyone learns to ignore them.
Why this SSL certificate expiry checker is different
Most certificate monitoring tools trap the useful functionality behind a sales call, a per-host price, or a required agent install. We rebuilt the experience from scratch so none of that exists. The free plan covers up to 10 hostnames permanently — enough for personal projects, side businesses, small SaaS apps, and most solo founders — with no credit card and no upsells. Authentication is frictionless: sign in with Google, Microsoft 365, GitHub, or a one-tap 10-minute magic link sent to your inbox. There are no passwords to manage. For teams that outgrow the 10-host limit, the free plan keeps working as long as you stay under it, and we send a transparent plan-limit error before any extra hostnames are saved — never a silent failure.
Onboarding in under 30 seconds
Sign up with your work email, confirm your company name, paste your first hostname into the dashboard, and you are protected. From there you can add more hostnames one at a time, or drop a CSV of every endpoint you own and we monitor them all in one pass. Each hostname goes through the same SSL certificate expiry date check we use for the public checker — issuer, valid-from, valid-to, signature algorithm, SAN list — and gets stored alongside the last known fingerprint so that any future change is detected. If you manage thousands of certificates, the REST API and webhooks let you pipe every state change into Slack, PagerDuty, or your incident management tool without ever opening the dashboard.
Why SSL certificate expiry is a security vulnerability to fix proactively
Security is the obvious reason to monitor SSL certificate expiry, but it is not the only one. A certificate that expires in the middle of a checkout flow costs revenue, search ranking, and customer trust in a single afternoon. Modern browsers and search engines treat certificate health as a ranking signal; a publicly observable expiry can quietly demote a page for weeks after the certificate is replaced. Outages are the loud symptom, but the silent loss is the bigger one. Treating SSL certificate expiry as a known vulnerability to fix proactively — with a monitored reminder list rather than a calendar entry that one engineer owns — is how mature teams operate. A proactive SSL certificate expiry alert is the cheapest insurance policy you can buy for your web presence, and the ROI compounds with every certificate you add.
Built out of necessity
We built Monitor SSL Certificates because we missed a renewal once, and we did not want it to happen again. The product is opinionated: it does one thing, it does it well, and it is honest about its limits. No dark patterns, no surprise upgrades, no telemetry of your certificates leaving our infrastructure. If you need to monitor SSL certificate expiry automatically for a single domain, a staging environment, or a thousand microservices, this is the tool. Start free, run it forever on up to 10 hostnames, and never see a broken padlock on your own site again.
Pricing
One plan. Free, forever.
No tiers, no upsells. Monitor up to 10 hostnames on the free plan and pay nothing — today or ever.
Free
$0
forever, up to 10 hostnames
Start free- ✓ Up to 10 hostnames
- ✓ Email alerts (30/15/7/1/0 days)
- ✓ Public SSL checker
- ✓ SSO + magic-link sign-in
- ✓ CSV bulk upload
- ✓ No credit card required
FAQ
SSL certificate expiry monitoring questions, answered.
How to continuously monitor SSL certificates?+
Sign up for a free Monitor SSL Certificates account, add up to 10 hostnames, and we connect on port 443 every 12 hours to read the certificate chain. Whenever the issuer, valid dates, signature algorithm, or subject alternative names change, we log the event. As the notAfter date approaches, we send SSL certificate expiry alerts by email at 30, 15, 7, 1, and 0 days before expiry so you have time to renew.
Why monitor SSL certificates?+
An expired certificate drops HTTPS back to HTTP, browser warnings like NET::ERR_CERT_DATE_INVALID scare users away from your checkout, search engines demote your rankings, and payment APIs return errors. Monitoring SSL certificate expiry turns the only predictable web-platform outage into a non-event — your team gets a heads-up days before the expiry date instead of waking up to a broken site.
How to continuously monitor SSL/TLS certificates?+
Use a dedicated SSL certificate expiry monitoring tool like Monitor SSL Certificates: add each hostname you own, pick the alert cadence (we default to 30 / 15 / 7 / 1 / 0 days), and let an external system poll the certificate on a fixed schedule. For internal certificates behind a firewall, run a lightweight agent on the same network so the monitor can reach port 443 without going through the public internet.
Start monitoring SSL certificates in under 30 seconds.
No credit card. No agent to install. Just paste a hostname and our SSL certificate expiry monitoring tool will watch the certificate for you.