Coincidentally this appeared on Facebook this afternoon. Unsure if this is an opinion or fact….
How do "I'm not a robot" checkboxes actually work?
Take a guess, and then get the answer. Is it based on your ability to click the box? How long you take to scroll? Or....?
When you check the "I'm not a robot" box on a reCAPTCHA, it’s not checking whether you can click a button. Here’s how it really works:
1. Analyzing Your Browser and Request Data
reCAPTCHA examines details about your browser and the information it sends with your request. Bots often use automated or unconventional browsers, which can be identified by analyzing browser headers and other metadata. Google’s extensive tracking network also helps verify legitimate users by recognizing familiar browsing patterns from other sites.
2. Observing Mouse Movements and Keystrokes
Human behavior, like mouse movements, clicks, and typing patterns, is tracked. Bots often perform these actions unnaturally—moving instantly to a specific area or clicking and releasing buttons too quickly. reCAPTCHA detects these discrepancies by analyzing timing and movement, which helps confirm you’re human.
3. Executing Browser Code
The script runs code from Google servers in your browser and expects a specific response within a short timeframe. Automated bots often struggle to mimic this behavior accurately, particularly if the code relies on hidden metrics tied to user interaction.
4. Scoring Likelihood of Being a Bot
Based on all the data collected, reCAPTCHA assigns a score indicating how likely you are to be a bot. If the score is below a certain threshold, you’ll be prompted to complete additional tasks like identifying images or solving a traditional CAPTCHA.
If you interact too quickly or don’t provide enough data (e.g., no mouse movements or keystrokes), the system may assume you’re a bot and require further verification. That’s why taking a moment to click the box after completing a form can help you avoid additional challenges — like the annoying photo selectors
