How Behavior‑Based Captchas Boost Security and User Experience

Project Overview

The behavior captcha is delivered as an embeddable component that can be integrated with minimal effort. It replaces the traditional character‑based verification (display‑input‑compare) with a workflow that shows a visual challenge, records user behavior (dragging or clicking), and analyzes the behavior to determine whether the interaction is human. The component can be displayed as a popup to avoid affecting the existing UI layout.

Captcha Types

Slide puzzle (blockPuzzle) – user drags a puzzle piece to complete a missing area.

Click‑word (clickWord) – user clicks specific characters or words displayed in the image.

Key Terminology

Verification attempt – each drag or click action counts as one verification attempt, regardless of success.

Secondary verification – after the form is submitted, the backend must call captchaService.verification to validate the captured behavior data.

Interaction Flow

User visits the application page and requests the behavior captcha.

User completes the displayed challenge (slide puzzle or click‑word) according to the instructions.

When the user submits the form, the frontend sends the challenge output together with other form fields to the backend.

The backend receives the data and invokes captchaService.verification for secondary verification.

The verification result (pass or fail) is returned to the application and reflected on the frontend.

Project Directory Structure

├─core
│ ├─captcha    java core source
│ └─captcha-spring-boot-starter  spring‑boot starter
├─images       demo images
├─service
│ ├─springboot   backend Spring‑Boot example
│ └─springmvc   backend Spring‑MVC (non‑Boot) example
└─view       multilingual client examples
 ├─android   native Android demo
 ├─flutter   Flutter demo
 ├─html     native HTML demo
 ├─ios      native iOS demo
 ├─uni‑app   uni‑app demo
 └─vue     Vue demo

Online Demo

PC demo: https://captcha.anji-plus.com/

WeChat Mini‑Program and H5 demos (based on uni‑app) are also available.