HTTPS
HTTPS is the encrypted version of HTTP, secured by a TLS certificate. It protects data travelling between browser and server from interception. Google confirmed it as a lightweight ranking signal in 2014, and browsers now warn users about sites without it.
Why it matters for your rankings
HTTPS is table stakes rather than an advantage. The ranking benefit is small, but the absence is costly: browsers display 'Not secure' next to your address, which destroys trust before anyone reads a word.
The subtle failures cause more damage than missing certificates. Mixed content, where an HTTPS page loads images or scripts over HTTP, triggers browser warnings and can block resources entirely. Expired certificates take sites down completely and often go unnoticed until traffic collapses. Migrations from HTTP done without redirecting every URL leave two indexable copies of the site competing with each other. Each of these is a self-inflicted wound that a single scheduled check would have prevented.
How to check it on your site
Test the certificate
Run your domain through SSL Labs. Anything below an A grade, or an expiry inside 30 days, needs attention.
Find mixed content
Open DevTools Console on key pages and look for mixed content warnings, or crawl with Screaming Frog's Insecure Content report.
Verify redirects are complete
Every http URL should 301 to its https equivalent in a single hop, including www variants.
Set a renewal reminder
Certificate expiry is the most avoidable outage in web operations. Automate renewal and alert on failure.