Question

I've notised that Stack Overflow only presents me with a captcha occasionally. Does anyone know if it has a good algorithm for sensing if I might be a robot or, instead if it's just random.

Reducing reliance on captchas is obviously a good thing.

Was it helpful?

Solution

Stackoverflow.com uses reCAPTCHA. And, I too have noticed that when you try to edit the same question many times in a gap of a few seconds, it displays the captcha verification page.

Most of the CAPTCHA generation algorithms are strong enough. This article describes the factors influencing a CAPTCHA's strength.

OTHER TIPS

My impression is that SO monitors user's activity and presents captcha in case of suspicious beaviour, for example in case of frecuent posts or comments.

It appears when you post (or edit) the same entry or an entry in the same question many times. It had appeared to me when I edit twice in less than a minute

I've never been confronted with a Captcha at SO because I used a google account and have not given it any reason to suspect me of being a bot I guess. If you don't create local logins you save yourself the trouble of Captcha and storing passwords.

EDIT I have now seen several captchas on the site, don't really have any idea what triggers them.

Licensed under: CC-BY-SA with attribution
Not affiliated with StackOverflow
scroll top