Audio captcha solver: How to bypass audio reCAPTCHA and any other audio captcha

audio captcha solver

2Captcha launched an audio recognition service. The audio method can be used to bypass audio captchas or to recognize any audio record. The service uses an automatic audio recognition system.

Motivation: Audio captchas typically restrict access to services and information based on our social and cultural backgrounds, physical and cognitive abilities, the devices or networks we connect from, and other criteria. An audio recording can be converted to text using auditory recognition technology. Audio recognition method allows to convert an audio record to text.

The limitations are:

  • Maximum file size: 1 megabyte
  • Audio duration: not limited
  • Supported audio format: mp3 only
  • Supported speech languages: English, French, German, Greek, Russian, Portuguese

The recognition is fully automated and performed by a neural network trained for speech recognition.

How to recognize audio to text

To recognize audio in text, you need to execute 2 queries:

  • Submit a file for recognition;
  • Get a result.

Submit a file

sending request to audio recognition

Collect the audio captcha parameters.

Audio recognition method allows bypassing the audio captcha challenge automatically.

To successfully bypass the captcha user need to send values:

  • body - base64 encoded audio file in mp3 format
  • lang - the language of audio record

Interact with audio captcha bypass API

When you have all required values submit the captcha to in.php endpoint of API with the following parameters:

parameter description
key API key
method audio - indicates that sending audio
body base64 encoded audio file in mp3 format
lang The language of audio record. Supported languages are:
'en': English
'fr': French
'de': German
'el': Greek
'pt': Portuguese
'ru': Russian

Request body example:

{
    "key":"xxxxx",
    "method":"audio",
    "body":"",
    "lang":"pt",
    "json":1
}

If everything is OK you will receive the response with your request ID.

Example:

{
   "status":1,
   "request":"xxxxx"
}

If the file upload failed, an error response should be returned. A list of all errors with a description is collected here.

To recognize an audio user needs to encode the mp3 file to base64.

Make a 15-20 seconds timeout then submit a HTTP GET request to API URL res.php to get the result.

Get a result

receiving a response with recognized text

Use the returned id of audio captcha to make request to res.php API endpoint with the following parameters:

col description
key API key
action get - get the answer for captcha
id ID of captcha returned by in.php

Example:

{
    "key":"xxxxx",
    "action":"get",
    "id":5
}

If audio captcha is already recognized server will return the text in the following format:

{
    "status": 1,
    "request": "hello world"
}

If the recognition process is not finished yet, the server will return CAPCHA_NOT_READY result.

If something goes wrong, the server will return an error code.

A list of all errors with a description is collected here.

Pricing

The price for 1000 recognitions is $0.5.

Audio captcha recognition code examples:

FAQ
API docs