Character encoding checker
A missing charset is how “São Paulo” becomes “São Paulo”. The browser should not have to guess.
What we measure
We read <meta charset> (or the http-equiv equivalent). Missing is a warning. UTF-8 is what you want on a public page today.
Where it goes
Put <meta charset="utf-8"> as the first element inside <head>, before any title or script that might contain non-ASCII. A charset declared after the first 1024 bytes can be ignored.
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