I'm not a big fan. They're often hard to read even for someone with reasonably normal vision.
"Is that a zero or the letter O?"
"Upper case C or lower case c?"
Others have suggested some sort of simple logic question, like asking "What's 1+1" and having the user enter a '2' in a text box.
That might be better, but it also requires some thought.
So I noticed that on Slideshare they prefix a captcha device with the question, "Are you human?"
And it got me thinking, can bots deal with radio buttons? Can we ask a question like this?
[syntax,human_form.htm,html4strict]
I must admit I haven't done any research, but I'm thinking:
- If a bot doesn't understand radio buttons it will skip the question and fail
- If it does understand radio buttons, it will probably choose the first option and fail
- It's an extremely simple question for a human to answer and should be completely accessible.
Point 2 is probably the most contentious. I'm making a big assumption there.
Has anyone else tried this? Can anyone spot any obvious disadvantages?
Haven't heard of that one before - but that's a pretty good idea. As long as you're careful what you name it, it's an unobtrusive method. Good call.
ReplyDeleteThis is funny, I just ran into some problems with spam bots posting one of my client's forms, and thought of this same solution after researching other methods.
ReplyDeleteHave you had any success with this?
Regardless I'm going to try it out as it seems the absolute simplest solution. The forms only get posted to me and my client (since that is all I allow server-side!), but they are still annoying.