No single check decides. A site scores the visit: what network the address belongs to, whether the browser's details fit together, how fast pages are requested, whether the mouse moves. A high score brings a captcha or a block.
A proxy only answers the first question, the address. If the browser itself gives the program away, a clean address will not help. This is why people pair proxies with a real browser, sensible speeds and, for separate accounts, an antidetect browser.
Questions about bot detection
Can a proxy alone get past bot detection?
Only where the address was the problem. Where the browser or the behaviour gives a script away, the proxy is one part of the answer and a real browser is the other.
Why do I see more captchas through a proxy?
The site trusts that address less, often because other users of it sent many requests. A different kind of address, usually residential or mobile, lowers the count.
Related terms
- Browser fingerprint
- A browser fingerprint is the mix of details a browser reveals, such as screen size, fonts and graphics card, that together single it out.
- TLS fingerprint
- A TLS fingerprint is the pattern in how a program opens an encrypted connection. It reveals whether the visitor is a browser or a script.
- Captcha
- A captcha is a test a website shows to check that a visitor is a person, such as picking images or ticking a box, before letting them continue.
- IP reputation
- IP reputation is the trust a website places in an IP address, based on who owns it and how addresses like it have behaved before.
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