User-Agent Sniffing Criticism

Comments criticize user-agent string detection as unreliable, hacky, and outdated, advocating for alternatives like Client Hints or freezing/removing UA strings entirely.

📉 Falling 0.5x Web Development
2,388
Comments
20
Years Active
5
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#3937
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Activity Over Time

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Keywords

US JS mobiforge.com KHTML mozilla.org modernizr.com WEI CH i.e AppleWebKit user agent agent user browsers strings detection string browser sites chrome

Sample Comments

nerd_in_rage Nov 6, 2012 View on HN

Good. User-Agent detection has always been a hack.

notatoad Mar 6, 2018 View on HN

nope, user agent sniffing is alive and well. Google is especially guilty, but lots of sites do it. Try changing your user agent and see how many things break.

rampr Sep 10, 2012 View on HN

Offtopic though, You might want to read how user agent strings have evolved - http://webaim.org/blog/user-agent-string-history/

gtirloni May 16, 2018 View on HN

Totally agree.https://developer.mozilla.org/en-US/docs/Web/HTTP/Browser_de...

technomancy Mar 14, 2015 View on HN

User agent sniffing? Seriously? I thought that died the death it deserved a decade ago.

JohnFen Jul 17, 2024 View on HN

User-agent isn't nearly reliable enough to do that with.

dehrmann Jun 27, 2020 View on HN

User agent isn't reliable enough to do this and definitely wasn't intended to be used this way, so you're just asking for brittle code. Supposedly Chrome is freezing its user agent very soon, so it's not even a good path going forward.

jrockway Feb 22, 2019 View on HN

It is probably time for browsers to stop sending a user agent string.

steveax Aug 31, 2013 View on HN

User agent sniffing is unreliable and evil.

stephenr Mar 18, 2024 View on HN

Tying your entire web app to user agent sniffing. What could possibly go wrong!?