Facebook Pixel Checker
Most free pixel checkers only read the page source, so if your pixel was installed through Google Tag Manager they tell you it is missing when it is sitting right there. This one opens the container and reads inside it. Paste your address and get a straight answer.
Conversion Tracking Checker
The expensive failure is not a missing pixel. It is a pixel that has been sitting there for two years reporting PageView and nothing else, so every ad looks equally good and none of them can be judged. This checks whether anything beyond a page view is ever reported.
Google Tag Manager Checker
Tag Manager is where tracking usually hides. If a pixel or an analytics tag seems to be missing from your page source, it is very often inside a container instead. This finds the container, shows its ID, and opens it to report what is loading inside.
Consent Mode v2 Checker
If you advertise to anyone in the EEA or the UK, Google requires consent signals to be sent with your tags. Without them, remarketing audiences stop filling and conversion modelling stops working for that traffic. A cookie banner on its own does not do this. This checks whether the signal is actually there.
Google Analytics Checker
Analytics is the cheapest thing on this list to install and the one most often half done: installed on the home page, missing on the pages that matter, or loading twice. This checks whether GA4 is running on the address you give it, including when it loads through a tag manager.
Google Ads Tag Checker
If you are paying Google for clicks and the Ads tag is missing, the campaign has no idea which clicks turned into anything. This finds the tag, including when it is fired from inside a Tag Manager container rather than written into the page.
What Is This Website Built With
Every website builder leaves fingerprints in the page it ships. This reads them and tells you which one made the site, whether it is still on the builder's own free address, and what that implies about moving it.
Mobile Friendly Checker
Google retired its own Mobile-Friendly Test in December 2023 and now points people at Lighthouse instead, which is a developer tool. This is the quick version: it checks whether the page is set up to render at phone width at all.
HTTPS Checker
If a site does not load over HTTPS, Chrome puts a Not secure warning next to the address for every visitor. This checks whether that is happening to yours, and it takes about ten seconds.
Why these are free, and what the catch is
There is no catch and no signup, because there is no cost to me. These run on the same engine as my full website check, which is ordinary code reading a public page. It costs nothing to run whether one person uses it or ten thousand do, so gating it behind an email would buy me a worse tool and a smaller number of people who trust it.
What I get is that some of the people who find something broken will ask me to fix it. That is the whole business model, and it only works if the answers are right.
The one thing these do that most free checkers do not
Most tags on a modern site are not in the page. They are inside a Google Tag Manager container, loaded after the page arrives. A checker that reads page source alone cannot see them, so it tells a business with a working pixel that it has none. The tracking checks here fetch the container and read through it.
And when a container is present but cannot be opened, the answer given is cannot tell, never no. A confident wrong answer to the one person who can check it is worth less than no answer at all.
This checks the page your address serves to a normal visitor, the same way a browser would, and it opens any Google Tag Manager container it finds and reads inside it. Nothing is stored, no signup is asked for, and the answer is the same one you would get by opening the page source yourself with more patience than most people have.