CaptchaSharp

A .NET library that implements the APIs of the most used captcha solving services out there. The library is fully documented, asynchronous and very easy to use.

All services derive from the same CaptchaService class and have the same code API, so it's very easy to switch between services!

Supported Services

This library supports the following captcha solving services

Supported Captcha Types

This library supports the following captcha types

Text (with language options)
Image (with options like phrase, case sensitivity, calculations)
ReCaptcha v2 (incl. invisible, enterprise)
ReCaptcha v3 (incl. enterprise)
ArkoseLabs FunCaptcha
HCaptcha (incl. invisible, enterprise)
KeyCaptcha
GeeTest v3
GeeTest v4
Capy
DataDome
Cloudflare Turnstile
Cloudflare Challenge page
Lemin Cropped
Amazon WAF
Cyber SiARA
MT Captcha
CutCaptcha
Friendly Captcha
atb Captcha
Tencent Captcha
Audio Captcha (with language options)
ReCaptcha Mobile

Additional supported features:

Proxies
User-Agent
Cookies

Availability Table

Availability Table Logo

Not every captcha type is supported by each service! You can find a spreadsheet with a breakdown of the supported captcha types for each implemented service at the link below

CaptchaSharp Services Availability

Adding CaptchaSharp to your project

Simply install the nuget package via

Install-Package CaptchaSharp

Usage

First of all, initialize your solver of choice by providing your credentials, for example

CaptchaService service = new TwoCaptchaService("MY_API_KEY");

You can get your remaining balance like this

decimal balance = await service.GetBalanceAsync();

If the provided credentials are wrong, the method above will return a BadAuthenticationException.

If the credentials are correct and the balance is greater than the minimum required for solving a captcha, you can proceed to solve a captcha (e.g., a ReCaptchaV2 task) like this.

StringResponse solution = await service.SolveRecaptchaV2Async("site key", "site url");

The method above can throw the following exceptions:

TaskCreationException when the task could not be created, for example due to zero balance or incorrect parameters.
TaskSolutionException when the task could not be completed, for example when an image captcha cannot be decoded.
TimeoutException when the captcha solution took too long to complete.

You can configure a custom timeout like this

service.Timeout = TimeSpan.FromMinutes(3);

The returned solution will contain two fields:

an Id which you can use for reporting a bad solution (if the service supports it) like this
```
await service.ReportSolutionAsync(solution.Id, CaptchaType.ReCaptchaV2);
```
if the report failed, the method above will throw a TaskReportException.

your solution as plaintext

Console.WriteLine($"The solution is {solution.Response}");

If a method or some of its parameters are not supported, a NotSupportedException or ArgumentException will be thrown.

Proxy, User-Agent, and Cookies

Some services and captcha types can accept additional parameters, like a proxy, user-agent, or cookies.

var sessionParams = new SessionParams
{
    Proxy = new Proxy(
        host: "proxy.example.com",
        port: 8080,
        type: ProxyType.HTTP,
        username: "proxy_username", // optional
        password: "proxy_password" // optional
    ),
    UserAgent = "Mozilla/5.0 ...", // make sure to use an up-to-date user-agent
    Cookies = new Dictionary<string, string>
    {
        { "cookie_name_1", "cookie_value_1" },
        { "cookie_name_2", "cookie_value_2" }
    }
};

// Solve a captcha with session parameters
StringResponse solution = await service.SolveRecaptchaV2Async(
    "site key", "site url", sessionParams: sessionParams);

Console.WriteLine($"The solution is {solution.Response}");

All session parameters are optional, and you can provide only the ones you need.

The service I want to use is not implemented

If the service you want to use is not implemented, you can easily implement it yourself by deriving from the CaptchaService class and implementing the abstract methods, or you can open an issue, and we will try to implement it as soon as possible.

Unit Tests

Unit tests are included in the CaptchaSharp.Tests project. In order to test, you need to:

Run any test once and let it fail. It will create a file called config.json in your bin/Debug/net8.0 folder.
Add your credentials to the config.json file. You can also add a proxy to test proxied endpoints.
Run the tests (one at a time, to avoid overloading the service and overspending).
If you need to test a captcha on a specific website, you can edit the ServiceTests class and change the parameters as you need.

What needs to be improved

Drop Newtonsoft.Json for System.Text.Json
Implement better exception handling for specific error codes. For example when there is zero balance or when a solver method returns a bad authentication, they will currently fall in the generic TaskCreationException type.
Add support for recognition APIs (right now only token-based APIs are supported).

openbullet / CaptchaSharp

readme