* Sites with an asterisk don't auto-populate the URL after clicking Test URL.
This will open a new tab or window for each of the test sites above. If only one test opens, your browser is blocking pop-ups. Allow pop-ups for chckr.co and try again.
Chckr is a list of some of the best website testing tools available for free.
No URLs are stored. The test buttons simply link out to the testing sites with the URL you want to check.
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