python requests.get() returns improperly decoded text instead of UTF-8?

Educated guesses (mentioned above) are probably just a check for Content-Type header as being sent by server (quite misleading use of educated imho).

For response header Content-Type: text/html the result is ISO-8859-1 (default for HTML4), regardless any content analysis (ie. default for HTML5 is UTF-8).

For response header Content-Type: text/html; charset=utf-8 the result is UTF-8.

Luckily for us, requests uses chardet library and that usually works quite well (attribute requests.Response.apparent_encoding), so you usually want to do:

r = requests.get("https://martin.slouf.name/")
# override encoding by real educated guess as provided by chardet
r.encoding = r.apparent_encoding
# access the data
r.text

From requests documentation:

When you make a request, Requests makes educated guesses about the encoding of the response based on the HTTP headers. The text encoding guessed by Requests is used when you access r.text. You can find out what encoding Requests is using, and change it, using the r.encoding property.

>>> r.encoding
'utf-8'
>>> r.encoding = 'ISO-8859-1'

Check the encoding requests used for your page, and if it's not the right one - try to force it to be the one you need.

Regarding the differences between requests and urllib.urlopen - they probably use different ways to guess the encoding. Thats all.

The default assumed content encoding for text/html is ISO-8859-1 aka Latin-1 :( See RFC-2854. UTF-8 was too young to become the default, it was born in 1993, about the same time as HTML and HTTP.

Use .content to access the byte stream, or .text to access the decoded Unicode stream. If the HTTP server does not care about the correct encoding, the value of .text may be off.