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Antonello Zanini
Antonello Zanini

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CapMonster Cloud Review: The All-in-One CAPTCHA Solving Service

Raise your hand if you think CAPTCHAs are annoying. Well, you’re not alone… For human users, CAPTCHA challenges are frustrating, but for automation workflows (e.g., web scraping bots or AI agents), they represent a serious roadblock!

That’s why, over the past few years, several CAPTCHA-solving services have popped up. They all promise to solve CAPTCHAs programmatically, but can they really deliver? Today, I’m reviewing CapMonster Cloud, one of the major players in the CAPTCHA-solving industry, to see if it lives up to the hype.

Follow me on this journey as I explain what the company is, the services they provide, how it all works with practical examples, their pricing, and—of course—a final verdict!

What Is CapMonster Cloud?

CapMonster Cloud is an online service that leverages artificial intelligence to quickly solve various types of CAPTCHAs in the cloud. Its solutions are designed for anyone who needs to bypass CAPTCHA challenges during web scraping, automation, or testing workflows.

CapMonster Cloud’s logo

This service is developed by ZennoLab, a company that provides a comprehensive suite of automation solutions.

CapMonster Cloud is trusted by over 1,000 businesses worldwide and has received excellent user feedback, including a 4.8/5 rating on Trustpilot, 5/5 on Slashdot, and 4.8/5 on SourceForge based on more than 120 verified reviews.

Main Features

These are the main features, capabilities, and aspects that characterize CapMonster Cloud:

  • AI-powered cloud-based CAPTCHA solving for automation tasks.
  • Reliable and fast API designed for high scalability.
  • Browser extensions for Chrome and Firefox for automatic CAPTCHA solving.
  • Ready-to-use SDKs in Python, JavaScript, C#, Go, and PHP.
  • Support for integration with external services.
  • Support for a wide range of CAPTCHA types, including reCAPTCHA v2/v3, Cloudflare Turnstile, DataDome, Tencent CAPTCHA, Amazon WAF, GeeTest, Imperva, Text CAPTCHAs, and others.
  • Ethical and transparent CAPTCHA automation principles.
  • Affiliate program available.
  • Fast and responsive customer support, available even on Telegram.

Product Lineup: CAPTCHA-Solving Solutions

Let me introduce the products offered by CapMonster Cloud API. Here, I’ll analyze how they work, the experience they provide, and their pros and cons.

For a quick overview, take a look at the summary table below:

Feature CapMonster Cloud API CapMonster Cloud Browser Extensions
Purpose Cloud-based CAPTCHA-solving service for automation and development Browser-based tool to automatically solve CAPTCHAs while browsing
Platform Any tool or programming language that can make HTTP requests Chrome and Firefox
Setup Call API endpoints authenticated with your CapMonster Cloud API key to send CAPTCHA data and receive the solution Install the extension, enter your API key, and let the extension solve the CAPTCHA for you

What I can say before diving into the details is that an API service and browser extensions are the two products you’d expect from a top-tier CAPTCHA solver. On top of that, as you’re about to discover, each comes with some unique perks that make them stand out.

Time to learn more!

CapMonster Cloud API

CapMonster Cloud API is a cloud CAPTCHA-solving service that automates CAPTCHA recognition and bypass. It exposes several HTTP endpoints so that you can send CAPTCHA data to the cloud and receive a solution in response. That’s ideal for developers seeking a programming language–agnostic CAPTCHA-solving solution.

In particular, the main endpoints exposed by CapMonster Cloud are:

Note: /getBalance and /getUserAgent are there only for account management and improving accuracy, respectively. While not strictly required, they’re a nice-to-have addition!

Given the available endpoints, this is how the CAPTCHA-solving process works:

  1. Create a task: Call /createTask with your Cloud Monster API key, the task type for your CAPTCHA type, and CAPTCHA details (e.g., key, URL, etc.). This API returns a taskId.
  2. Poll for a result: Poll /getTaskResult with your CapMonster Cloud API key. When the CAPTCHA-solving task finishes, the API will return a "ready" status and an object containing the solution for your task type (e.g., the text answer, a gRecaptchaResponse token, etc.).
  3. Use the solution: After receiving the solution, use it to solve the CAPTCHA or submit the token to validate the target site’s form, API call, page loading, etc.

As you can see, the process is pretty simple and similar to other CAPTCHA-solving services. So, nothing new here!

⚙️ Special features:

  • Extra endpoints for account management (/getBalance).
  • Public API (/getUserAgent) to fetch the User-Agent header set by the latest version of Chrome on Windows.

👍 Pros:

  • Supports ~20 different CAPTCHA types, each clearly documented and with snippets in C#, Python, JS, Go, and PHP.
  • Intuitive API-based workflow using only two main endpoints: /createTask and /getTaskResult.
  • Cloud-based, requiring no software installation, and usable from any programming language that can make HTTP requests.
  • Support for custom proxy integration.
  • Clear error descriptions, with technical support available via a support form, the Telegram channel, or live chat on the website.
  • High-level SDKs in Python, JavaScript, C#, Go, and PHP, so you don’t have to call the APIs directly.

👎 Cons:

  • Temporary bans (usually ~10 minutes) occur for repeated errors, such as requests without a key or with an invalid key, requests on a zero account balance, exceeding the task check limit (~120 per task), etc.

Browser Extensions

CapMonster Cloud also comes with dedicated browser extensions, which enable you to automatically solve CAPTCHAs encountered while browsing. These are available for Chrome and Firefox, and they connect to your CapMonster Cloud account via an API key.

The UI of the CapMonster Cloud extension

These extensions are perfect for professionals who want to save time and boost productivity by automating repetitive CAPTCHA challenges. Below is how they work:

  1. Install the extension in Chrome or Firefox.
  2. Enter your CapMonster Cloud API key and ensure your account balance is not zero.
  3. The extension automatically detects CAPTCHAs, sends them to the cloud, and fills in the solution in the background.

Quite easy, isn’t it!?

Also, they support developers who want to integrate them into browser automation tools like Selenium, Playwright, or Puppeteer. That's possible because the extensions can be downloaded as a local archive, allowing configuration and programmatic integration into browser instances controlled by automation scripts.

The two browser extensions also add a dedicated “CapMonster Cloud” tab in your browser’s DevTools. This tab displays details for the CAPTCHAs on the current web page, providing all the information you need to populate the body for /createTask requests:

Note the info in the “CapMonster Cloud” tab

As of this writing, the CapMonster Cloud extension for Chrome has over 20k downloads and a 4.3/5 rating based on 73 reviews.

⚙️ Special features:

👍 Pros:

  • Automates CAPTCHA solving, saving you time.
  • Works in the background without any user intervention.
  • Available in both Chrome and Firefox.

👎 Cons:

  • May have known issues detecting CAPTCHA keys hidden inside shadow DOMs in closed mode.

Hands-On: Solving a CAPTCHA with CapMonster Cloud

You know what CapMonster Cloud has to offer, but at the end of the day, what really matters is the developer experience and whether the CAPTCHA-solving solution actually works.

So, let’s not waste any more time and see CapMonster Cloud in action with a real-world CAPTCHA-solving scenario, both via the API and the browser extensions!

Before Setting Started

To follow along, make sure you have:

  • Python installed locally.
  • The CapMonster Cloud extension installed in your browser.
  • A CapMonster API key.

To get your CapMonster API key, sign up or log in, go to your dashboard, add some funds, and copy your API key:

Copying your API key

Store your API key in a safe place, because you’ll need it to integrate with CapMonster Cloud in both the API and browser extension walkthroughs.

Specifically, I’ll show you how to solve the CAPTCHA on Google’s reCAPTCHA demo page. There, a reCAPTCHA v2 “I’m not a robot” checkbox prevents forms from being submitted by bots. Once the CAPTCHA is solved and the form is submitted correctly, you’ll see the “Verification Success… Hooray!” message:

The interaction in Google's reCAPTCHA demo page

For those not familiar with this challenge, the “I’m not a robot” checkbox is the most common version of reCAPTCHA v2. This is how it works:

  • If the user is deemed human, the checkbox displays a green checkmark, allowing them to proceed without further interaction.
  • If suspicious activity is detected, a visual challenge is presented (e.g., selecting all images containing a specific object, like a bus or traffic light).

reCAPTCHA v2 is one of the most widely used CAPTCHA types, typically associated with form submissions and anti-bot detection. Even Google itself uses it in its search pages when it suspects bot activity:

A Google reCAPTCHA v2 on a Google SERP

Let’s verify if CapMonster Cloud can handle it!

With CapMonster Cloud API

Once you know you’re dealing with a reCAPTCHA v2, start by taking a look at the official documentation.

💡 Pro tip: If you’re unsure which type of CAPTCHA you’re dealing with, you can check the info in the “CapMonster Cloud” tab from the browser extension, like I showed earlier.

For this example, the reference is the RecaptchaV2Task documentation page:

The “RecaptchaV2Task” documentation page

The documentation is thorough and includes all the details you need to solve this type of CAPTCHA. Don’t worry, though. If you need more guidance, the CapMonster Cloud blog has step-by-step guides for all supported CAPTCHA types. For example, take a look at these two blog posts:

For reCAPTCHA v2, the required body for the /createTask API endpoint looks like this:

    {
      "clientKey":"<YOUR_CAPMONSTER_CLOUD_API_KEY>",
      "task": {
            "type":"RecaptchaV2Task",
            "websiteURL":"<WEB_PAGE_URL>",
            "websiteKey":"<PUBLIC_RECAPTCHA_KEY>"
      }
    }
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In other words, you need to retrieve the websiteKey from the target page. This is the site’s API key used to load the CAPTCHA and is embedded directly in the page. You can find that by exploring the DOM (e.g., search for "key" or similar):

Retrieving the websiteKey info

Or, to save time, you can use the “CapMonster Cloud” tab in your browser’s DevTools, as shown earlier. It’s always nice to have multiple options!

In this case, the body for the /createTask API call looks like this:

{
  "clientKey":"<YOUR_CAPMONSTER_CLOUD_API_KEY>",
  "task": {
        "type":"RecaptchaV2Task",
        "websiteURL":"https://www.google.com/recaptcha/api2/demo",
        "websiteKey":"6Le-wvkSAAAAAPBMRTvw0Q4Muexq9bi0DJwx_mJ-"
  }
}
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That’s literally all the info you need to solve a reCAPTCHA v2 using CapMonster Cloud. Pretty simple, right?

Now, get ready to verify that the CAPTCHA-solving functionality works. For a simplified setup, I’ll use the official CapMonster Cloud Python SDK.

First, install it with:

pip install capmonstercloudclient
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Then, you can utilize it to solve a CAPTCHA with just a few lines of code:

import asyncio
from capmonstercloudclient import CapMonsterClient, ClientOptions
from capmonstercloudclient.requests import RecaptchaV2Request

# Replace it with your CapMonster Cloud API key or read it from the envs
CAPMONSTER_CLOUD_API_KEY = "<YOUR_CAPMONSTER_CLOUD_API_KEY>"

async def main():
    # Initialize a CapMonster Cloud API client
    capmonster_client_options = ClientOptions(api_key=CAPMONSTER_CLOUD_API_KEY)
    capmonster_client = CapMonsterClient(options=capmonster_client_options)

    # Request CAPTCHA solving from the cloud
    request = RecaptchaV2Request(
        websiteUrl="https://www.google.com/recaptcha/api2/demo",
        websiteKey="6Le-wvkSAAAAAPBMRTvw0Q4Muexq9bi0DJwx_mJ-"
    )
    response = await capmonster_client.solve_captcha(request)
    print(response)

if __name__ == "__main__":
    asyncio.run(main())
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Behind the scenes, solve_captcha() does all the heavy lifting for you:

  1. Creates a RecaptchaV2Task with the given CAPTCHA details by calling the createTask API endpoint.
  2. Polls the /getTaskResult endpoint until the solution is ready.
  3. Returns the final token.

That's precisely the same API-based CAPTCHA solving flow we discussed earlier.

response will look something like this:

{
  "gRecaptchaResponse": "0cAFcWeA6nLpY..."
}
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gRecaptchaResponse is the token you get after solving a reCAPTCHA.

To complete the flow, you need to programmatically simulate the form submission on the target page, like so:

# pip install requests
import requests

# CAPTCHA solving code...

# Exract the solutuon token from the response 
g_recaptcha_response = response.get("gRecaptchaResponse")

# Simulate the form submission on the target page
page = requests.post(
    "https://www.google.com/recaptcha/api2/demo",
    headers={
        "Content-Type": "application/x-www-form-urlencoded",
    },
    data={
        "g-recaptcha-response": g_recaptcha_response
    },
)

# Retrieve the HTML document from the response and print it
html = page.text
print(html)
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The result will be the HTML of the verification success page, confirming that the CAPTCHA was solved correctly (note the “Verification Success… Hooray!” message):

The HTML output produced by the script

Mission complete! CAPTCHA solved, all with just a handful of lines of code.

With Browser Extensions

Open the CapMonster Cloud extension, make sure it’s set to “On”, paste your API key into the designated field, and hit the save button:

Setting your CapMonster Cloud API key in the browser extensio

Your account balance will also be displayed in the extension UI, so you can always check it at a glance:

Your account's balance is always there

That’s a nice touch since you don’t want to run out of credits mid-task. This simple feature lets you keep an eye on them.

Next, make sure “ReCaptcha2” solving is enabled, set to “Click”, and that the “Auto solve” and “Auto click” options are turned on:

Pressing the

No need to go into detail about these options, as they’re pretty straightforward.

Visit the target page, and you’ll see the CAPTCHA get automatically checked (note that the mouse pointer doesn’t move):

CapMonster Cloud Chrome extension solving the reCAPTCHA v2

That wasn’t magic—it’s just the CapMonster Cloud extension doing its job!

Now, press the “Submit” button, and you’ll see that the CAPTCHA has been solved successfully:

Manually clicking the “Submit” button after CAPTCHA solving

If you don’t want to click “Submit” manually, you can right-click, access the context menu, and select the “Select element for submit” option:

Enabling the “Select element for submit” option

This way, the extension will detect the button and handle it automatically, saving you an extra click.

Amazing! There’s not much to comment here, as the experience is as effortless as you could hope for...

➡️ Want to bring this seamless CAPTCHA-solving experience into your automated browser scripts? Check out the official guide: “Integrating the Extension into Selenium using Node.js.”

Pricing Breakdown and Competitor Comparison

CloudMonster Cloud charges per CAPTCHA solved, following this pricing table:

CAPTCHA Type Pricing
reCAPTCHA v2 $0.04 per 1k images, $0.60 per 1k tokens
reCAPTCHA v3 $0.90 per 1k tokens
reCAPTCHA Enterprise $0.04 per 1k images, $1.00 per 1k tokens
GeeTest $1.20 per 1k tokens
Cloudflare Turnstile $1.30 per 1k tokens
Cloudflare Bot Challenge $1.30 per 1k tokens
DataDome $2.20 per 1k tokens
Tencent CAPTCHA $1.60 per 1k tokens
Amazon WAF $1.40 per 1k tokens
Faucet Pay $1.00 per 1k tokens
Imperva (Incapsula) $2.00 per 1k tokens
Prosopo $1.30 per 1k tokens
Text CAPTCHA $0.30 per 1k tokens
Temu $2.00 per 1k tokens
Yidun $1.00 per 1k tokens
MTCaptcha $1.50 per 1k tokens
Altcha $0.80 per 1k tokens

🚨 Important: Proxy traffic used by the Cloud solver for non-proxyless CAPTCHA tasks is included in the above prices.

In other words, to make things simple, every time you use CloudMonster Cloud to solve a reCAPTCHA v2, you pay $0.0006 per solution token (equivalent to $0.60 per 1,000 tokens). Put differently, $1 covers roughly 1,666 reCAPTCHA v2 challenges.

ℹ️ Note: Payment options are flexible and include PayPal, MasterCard, Visa, Wire transfers, cryptocurrencies, UnionPay, and MIR (payments in Russian rubles). So there’s really an option for everyone.

Based on my experience in the web scraping industry, these prices are competitive—among the best compared to other top CAPTCHA-solving providers. Considering that I achieved a 99% success rate in my tests, I believe CloudMonster Cloud is well worth the money you’re paying!

Final Verdict

In this review, I had the chance to try CapMonster Cloud in depth and see for myself whether it really is one of the best CAPTCHA-solving solutions available on the web.

The experience was fantastic. That's true for both developers using their API and SDKs, and regular users leveraging the browser extension to save time on CAPTCHA-heavy tasks. In both cases, the underlying AI-solving system doesn’t disappoint.

I’ve personally seen it work its magic a few times—like automatically selecting all the traffic lights in a reCAPTCHA challenge—saving a lot of manual effort. I imagine the same magic is applied in the cloud when solving CAPTCHAs via API

There are a few extra features worth noting, too. The CAPTCHA recognition tool available in the extension is a huge time-saver for developers. I also appreciated that the extensions are provided as downloadable archives, making it easy to integrate into browser automation setups.

Considering the competitive pricing, pay-for-success model, the long list of features, and the extensive documentation and blog posts, I can confidently say that CapMonster Cloud is one of the best CAPTCHA-solving services out there—and hands down the best I’ve personally tried!

Review score: 9.6/10

Final verdict

Top comments (2)

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federicotrotta profile image
Federico Trotta

Definitely, one of the best product reviews I have read so far in recent articles. Coincise, thorough, and clear. Also, seems like a great product: I'll definitely test it for my scraping projects. Thank you!!

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antozanini profile image
Antonello Zanini

Thanks, man! Appreciated it 😍