Captcha solving examples with JavaScript and Puppeteer

Examples of solving popular captcha types with @captcha-solver-api/javascript-sdk and Puppeteer.

Each example shows how to:

1. Open a page and collect captcha parameters.
2. Send a task to Captcha Solver.
3. Apply the solution in the browser.
4. Check that the page accepted the solution.

Installation

Requirements:

• Node.js 22.12 or newer
• A Captcha Solver API key with a positive balance

git clone https://github.com/captcha-solver-api/captcha-solver-puppeteer-javascript-examples.git
cd captcha-solver-puppeteer-javascript-examples
npm ci

On macOS and Linux, create the local configuration file with:

cp .env.example .env

On Windows PowerShell:

Copy-Item .env.example .env

Set your API key in .env:

CAPTCHA_API_KEY=your_api_key

Run

npm run example:recaptcha-v2

Chrome opens in visible mode. Set HEADLESS=true in .env to run it in the background. Every example launches Chrome through puppeteer-extra with puppeteer-extra-plugin-stealth, which reduces common automation fingerprints. Stealth is not a substitute for permission to automate a website.

Each run prints numbered steps, the CAPTCHA parameters sent to the API, the complete solution including its token, how the solution is applied, and the demo page's acceptance message. Image bodies are shown as their base64 length; API keys and proxy credentials are redacted.

Every example is intentionally self-contained and written as a linear tutorial: SDK and browser setup, page navigation, parameter collection, task creation, solver.solve(), solution application, form submission, and acceptance check are all visible in the same file. Some code is repeated so that an example can be copied without also copying hidden project helpers.

Examples

Captcha	File	Command
reCAPTCHA v2	recaptcha_v2.js	npm run example:recaptcha-v2
reCAPTCHA v2 + proxy	recaptcha_v2_proxy.js	npm run example:recaptcha-v2-proxy
reCAPTCHA v2 callback	recaptcha_v2_callback_variant1.js	npm run example:callback
reCAPTCHA v2 callback, automatic discovery	recaptcha_v2_callback_variant2.js	npm run example:callback-auto
reCAPTCHA v2 callback + proxy	recaptcha_v2_callback_proxy.js	npm run example:callback-proxy
reCAPTCHA v3	recaptcha_v3.js	npm run example:recaptcha-v3
reCAPTCHA v3 interception	recaptcha_v3_extended_js_script.js	npm run example:recaptcha-v3-extended
Cloudflare Turnstile	cloudflare_turnstile.js	npm run example:turnstile
Cloudflare Challenge	cloudflare_challenge_page.js	npm run example:challenge
Tencent CAPTCHA	tencent.js	npm run example:tencent
Yandex SmartCaptcha	yandex_smartcaptcha.js	npm run example:yandex-smartcaptcha
Image captcha, screenshot	normal_captcha_screenshot.js	npm run example:image
Image captcha, original pixels through canvas	normal_captcha_canvas.js	npm run example:image-canvas
Image captcha with parameters	normal_captcha_screenshot_params.js	npm run example:image-params
Coordinates	coordinates.js	npm run example:coordinates

The reCAPTCHA v2 and Yandex SmartCaptcha examples use the official provider demos by default. Every other browser example requires TARGET_URL in .env for a page you are authorized to test.

Proxy

PROXY_TYPE=http
PROXY_ADDRESS=proxy.example.com
PROXY_PORT=8080
PROXY_LOGIN=
PROXY_PASSWORD=

The browser and API task use the same proxy.

Checks

npm run lint
npm run check
npm test

normal_captcha_screenshot.js sends the pixels as rendered by Chrome. normal_captcha_canvas.js draws the loaded image into a canvas and sends its original pixel data, avoiding viewport scaling and screenshot effects. Canvas capture only works when the page permits reading the image without a CORS-tainted canvas.

Useful links

• Captcha Solver API documentation
• Captcha Solver JavaScript SDK
• Captcha Solver JavaScript Examples
• Captcha Solver Python SDK
• Captcha Solver Python Examples
• Selenium Python Examples
• Cloudflare Turnstile Puppeteer Demo
• Tencent CAPTCHA Automation Guide

License

This project is licensed under the MIT License.