GeeTest v3 Slider Parameter Extraction and Solving

GeeTest v3 slider CAPTCHAs require two parameters to solve: gt (a static site identifier) and challenge (a dynamic session token). This guide shows how to extract both from any page and submit them to CaptchaAI.

GeeTest v3 parameters explained

The gt value stays the same across requests. The challenge value changes every time the CAPTCHA loads — you must extract a fresh one for each solve attempt.

Method 1: Intercept the register API call

Most GeeTest v3 implementations fetch the challenge from a registration endpoint. The response looks like:

{
  "success": 1,
  "challenge": "a3f5c8d2e1b04a6789012345678abcdf",
  "gt": "019924a82c70bb123aae90d483b6a0ed",
  "new_captcha": true
}

Python (requests)

import requests
import re

session = requests.Session()
html = session.get("https://example.com/login").text

# Find the register endpoint
register_url = re.search(
    r'(https?://[^"\']+(?:register|captcha|geetest)[^"\']*)',
    html
)

if register_url:
    resp = session.get(register_url.group(1)).json()
    gt = resp["gt"]
    challenge = resp["challenge"]
    print(f"gt: {gt}")
    print(f"challenge: {challenge}")

JavaScript (Puppeteer network interception)

const puppeteer = require('puppeteer');

const browser = await puppeteer.launch();
const page = await browser.newPage();

let geetestParams = {};

page.on('response', async (response) => {
  const url = response.url();
  if (url.includes('register') || url.includes('captcha')) {
    try {
      const json = await response.json();
      if (json.gt && json.challenge) {
        geetestParams = {
          gt: json.gt,
          challenge: json.challenge,
        };
        console.log('Captured GeeTest params:', geetestParams);
      }
    } catch (e) {}
  }
});

await page.goto('https://example.com/login', { waitUntil: 'networkidle2' });
console.log('Final params:', geetestParams);

Method 2: Extract from page source

Some sites embed the parameters directly in HTML or inline scripts:

import re

# From data attributes
gt_match = re.search(r'data-gt=["\']([a-f0-9]{32})', html)
challenge_match = re.search(r'data-challenge=["\']([a-f0-9]{32})', html)

# From JavaScript variables
if not gt_match:
    gt_match = re.search(r'gt\s*[=:]\s*["\']([a-f0-9]{32})', html)
if not challenge_match:
    challenge_match = re.search(r'challenge\s*[=:]\s*["\']([a-f0-9]{32})', html)

gt = gt_match.group(1) if gt_match else None
challenge = challenge_match.group(1) if challenge_match else None
print(f"gt={gt}, challenge={challenge}")

Method 3: Hook initGeetest

GeeTest v3 initializes via initGeetest(). Intercept it before the page scripts run:

// Puppeteer: inject before page scripts
await page.evaluateOnNewDocument(() => {
  window.__geetestConfig = null;
  const origInit = window.initGeetest;

  Object.defineProperty(window, 'initGeetest', {
    set(fn) {
      this._initGeetest = function(config, callback) {
        window.__geetestConfig = config;
        console.log('GeeTest config:', JSON.stringify(config));
        return fn(config, callback);
      };
    },
    get() { return this._initGeetest; }
  });
});

await page.goto('https://example.com/login', { waitUntil: 'networkidle2' });

const config = await page.evaluate(() => window.__geetestConfig);
// config = { gt: "019924a...", challenge: "a3f5c8d...", product: "bind", ... }

Solving GeeTest v3 with CaptchaAI

Python

import requests
import time

API_KEY = "YOUR_API_KEY"

# Submit
resp = requests.post("https://ocr.captchaai.com/in.php", data={
    "key": API_KEY,
    "method": "geetest",
    "gt": gt,
    "challenge": challenge,
    "pageurl": "https://example.com/login",
    "json": "1",
}).json()

if resp["status"] != 1:
    raise Exception(f"Submit error: {resp['request']}")

task_id = resp["request"]

# Poll
for _ in range(30):
    time.sleep(5)
    result = requests.get("https://ocr.captchaai.com/res.php", params={
        "key": API_KEY, "action": "get", "id": task_id, "json": "1"
    }).json()

    if result["status"] == 1:
        solution = result["request"]
        print(f"Solution: {solution}")
        break
    if result["request"] != "CAPCHA_NOT_READY":
        raise Exception(f"Error: {result['request']}")

JavaScript

const submit = await axios.post('https://ocr.captchaai.com/in.php', null, {
  params: {
    key: 'YOUR_API_KEY',
    method: 'geetest',
    gt: geetestParams.gt,
    challenge: geetestParams.challenge,
    pageurl: 'https://example.com/login',
    json: 1,
  }
});
const taskId = submit.data.request;

let solution = null;
for (let i = 0; i < 30; i++) {
  await new Promise(r => setTimeout(r, 5000));
  const poll = await axios.get('https://ocr.captchaai.com/res.php', {
    params: { key: 'YOUR_API_KEY', action: 'get', id: taskId, json: 1 }
  });
  if (poll.data.status === 1) {
    solution = poll.data.request;
    break;
  }
}
console.log('Solution:', solution);

Injecting the GeeTest solution

The CaptchaAI response for GeeTest v3 includes challenge, validate, and seccode:

# solution is a pipe-delimited string or JSON object
# Parse and inject into the form
import json

sol = json.loads(solution) if isinstance(solution, str) else solution

driver.execute_script("""
    const form = document.querySelector('form');
    function addHidden(name, value) {
        let input = form.querySelector(`input[name="${name}"]`);
        if (!input) {
            input = document.createElement('input');
            input.type = 'hidden';
            input.name = name;
            form.appendChild(input);
        }
        input.value = value;
    }
    addHidden('geetest_challenge', arguments[0]);
    addHidden('geetest_validate', arguments[1]);
    addHidden('geetest_seccode', arguments[2]);
""", sol["challenge"], sol["validate"], sol["seccode"])

Troubleshooting

FAQ

How long is a GeeTest challenge valid?

Typically 60-120 seconds. Extract the challenge and submit to CaptchaAI immediately.

What's the difference between GeeTest v3 and v4?

GeeTest v3 uses gt/challenge parameters and a slider. GeeTest v4 uses captcha_id and has multiple challenge types (click, match, slide).

Solve GeeTest v3 CAPTCHAs with CaptchaAI

Get your API key at captchaai.com.

Related guides

• Browser Console CAPTCHA Detection
• Extracting reCAPTCHA Parameters
• Cloudflare Turnstile Sitekey Extraction