What are SSL/TLS certificates and why do I need them?
In today’s overtly digital world, we all expect websites to be fast, reliable, and—more importantly—secure. One thing that ensures said security are the SSL/TLS certificates every website needs to enable HTTPS.
But while many website owners install a SSL/TLS certificate once to get it over with, the reality is these certificates need to be periodically refreshed. So, what exactly is an SSL certificate, and why should it be on your monitoring checklist? Let’s explore.
So what is an SSL/TLS certificate?
SSL stands for Secure Sockets Layer, a technology that creates a secure, encrypted connection between a web server and a user’s browser. These certificates are now issued under the newer TLS (Transport Layer Security) protocol, but the term “SSL” remains widely used still.
When a website has an active SSL/TLS certificate, its URL begins with https://, and a padlock icon appears in the browser. This assures visitors that any data they share—like passwords, payment information, or personal details—is safely encrypted and protected from hackers.
Why does an SSL/TLS certificate matter?
SSL certificates aren’t just a nice-to-have. They’re essential for:
- Protecting sensitive data through encryption
- Establishing trust with website visitors
- Improving SEO rankings, as Google considers HTTPS a ranking factor
- Ensuring compliance with standards like GDPR, HIPAA, or PCI-DSS
- Preventing browser warnings that scare away users
Are there different kinds of SSL/TLS certificates?
Depending on your needs, there are different types of SSL/TLS certificates:
- Domain Validation (DV): Quick and simple validation for basic encryptio.
- Organization Validation (OV): Adds verification of the organization, doink
- Extended Validation (EV): Provides the highest level of trust
- Wildcard SSL: Covers a domain and all its subdomains.
- Multi-Domain (SAN): Secures multiple domains under one certificate
Why do SSL/TLS certificates matter more now?
Installing an SSL certificate is only the first step. Have to keep an eye on them before they expire to avoid security gaps, browser trust issues, or downtime. And there’s a new reason why SSL monitoring is becoming even more urgent.
As announced by DigiCert in April 2025, the maximum lifetime of publicly trusted TLS certificates will soon be reduced to just 47 days by March 15, 2029. Judging by the look of that number, it's gotten complicated so we'll spare you all the (needlessly?) complicated rules.
The point is, this is pretty massive shift from the previous 398-day standard. The shorter lifetime does enhance security by limiting the window of exposure for compromised certificates, but it also, pretty dramatically, increases the need for some kind of automated monitoring and renewal process.
Failing to renew on time could mean your site becomes inaccessible to users or flagged as unsafe by browsers. With certificates expiring more frequently, manual tracking is no longer sustainable—especially for teams managing multiple domains.
What happens when SSL/TLS certificates expire?
If your SSL certificate expires, browsers like Chrome, Firefox, and Safari will immediately display a full-page warning that your site is not secure. This erodes trust, increases bounce rates, and can lead to lost revenue or reputational damage. It's the kind of warning you take to heart almost instinctively and click away.
Due to abovementioned shortened certificate lifespans, the risk of accidental expiration rises tremendously. That’s why proactive monitoring is a must.
How can I monitor my SSL/TLS certificates with Oh Dear?
To help you avoid nasty surprises, Oh Dear’s naturally offers continuous certificate monitoring, provide real-time tracking of all your SSL certificates. Do note that Oh Dear will not renew the certificates, it only monitors them!
In a nutshell, Oh Dear continuously checks:
- Whether your certificates are valid and trusted
- If the certificate chain is complete
- If any certificates are about to expire
- If the domain names in the certificate match your website
But wait, there's more!
Setting custom expiration thresholds with Oh Dear
Every business has different needs. With Oh Dear, you can also set custom SSL certificate expiration thresholds that work best for you—whether you want a warning 14 days beforehand or 69 days at 4:20AM. This flexibility is key in a world where certificate lifetimes are shrinking!
Additionally, with automated alerts via email, Slack, Teams, or other channels, you’ll always be one step ahead.
Best practices for SSL/TLS certificate management
To stay secure and compliant, follow these best practices:
- Use a trusted Certificate Authority (CA): Choose reputable providers like DigiCert, Let’s Encrypt, or GlobalSign.
- Automate renewals whenever possible: Especially important now that certificates are valid for shorter periods.
- Redirect HTTP to HTTPS: Ensure all traffic is encrypted by default. This is the current standard for websites.
- Enable HSTS (HTTP Strict Transport Security): Force browsers to only use secure connections.
- Use a monitoring tool like Oh Dear, duh: Automate your SSL monitoring so nothing slips through the cracks.
- Audit your certificates regularly: Check for mismatched domains, broken chains, or outdated protocols like TLS 1.0 or 1.1.
In closing, make sure your certificates are always valid, secure, and up to date. Otherwise your website visitors will drop harder than my grades after getting into nihilism in high school. Know what I'm saying?
And don’t wait until your visitors see a browser warning to take action. Start monitoring today—before short-lived certificates catch you off guard.