CAPTCHA Cracking Tools: Automatic Recognition Programs

A. Why CAPTCHA crack must use proxy IP?

Anyone who works with CAPTCHA understands that frequent requests to the target site are likeOpen the door a thousand times with the same key.The first thing you need to do is to get a proxy IP to be able to access the site and to be able to do so. This time it is necessary to rely on proxy IP tomasquerading as different users, especially service providers like ipipgo that can offer a huge number of residential IPs that are harder to recognize than regular server room IPs.

Take a real case: an e-commerce platform uses the same IP to request 50 times in a row to block the number. After switching to ipipgo's dynamic residential IP pool, by automatically switching different city IPs, the request success rate soared from 30% to 92%.

import requests
from ipipgo import get_proxy This is assuming the official ipipgo SDK.

def crack_captcha(url).
    proxy = get_proxy(type='residential') get residential proxy
    session = requests.Session()
    session.proxies = {"http": proxy, "https": proxy}

     Get the CAPTCHA image first
    img_data = session.get(url+'/captcha').content

     Call the recognition interface (here you have to replace it with your own recognition service)
    result = ocr_service(img_data)

     Submit the result
    resp = session.post(url+'/login', data={'code': result})
    return resp.status_code

II. The core three axes of the automatic identification program

First Axe: IP Rotation Strategy
RecommendedToggle by number of failuresInstead of a fixed frequency: when 3 consecutive recognition failures occur, immediately change ipipgo's proxy IP. this saves IP resources more than a timed switch.

Axe 2: Request for fingerprint disguise
These parameters must be changed to match the proxy IP:
- User-Agent random library (prepare at least 200 common browser UAs)
- Network latency jitter (random within ±300ms)
- HTTPS certificate fingerprinting (with ipipgo's residential proxy comes with real device fingerprinting)

Axe 3: Multi-Engine Hybrid Recognition

Third, how to operate specifically? Hands-on teaching

Step 1: Configure the ipipgo proxy pool
Created in the backend of the official websiteDynamic Residential IPproject, it is recommended to selectMixed territoriesMode. Remember these two parameters:
- Authentication method: username + password (more stable than API)
- Session hold time: 120 seconds (too short will result in dropping out mid-session)

Step 2: Build the Local Agent Middleware
Don't use the requests library directly, it's recommended to use theScrapy MiddlewareDoing automatic IP switching. Key code snippet:

class IpipgoProxyMiddleware.
    def process_request(self, request, spider).
        request.meta['proxy'] = "http://user:pass@gateway.ipipgo.com:8000"
         Randomly change the exit city for each request
        request.headers['X-City-Code'] = random.choice(['BJ','SH','GZ']) 

Step 3: CAPTCHA Recognition Service Docking
recommendedFailure Retry + Confidence FilteringMechanism: When the recognition confidence is lower than 85%, the result is automatically discarded and the CAPTCHA is reacquired to avoid account blocking due to low quality recognition.

iv. guide to demining common problems

Q: Why is it still recognized after using a proxy IP?
A: 90% becauseBrowser fingerprints aren't handled properlyIt is recommended to replace requests with modern frameworks such as playwright, which works better with ipipgo's mobile 4G proxy.

Q: How to break Google reCAPTCHA when I encounter it?
A: Don't get hard! On ipipgo'sU.S. Residential IP+ automated mouse track simulation, the success rate can be up to 70%. Remember to clear your browser cache regularly and process up to 3 verifications per IP.

Q: How do I assess how many proxy IPs I need?
A: Remember the formula:
Number of IPs required = Average daily requests ÷ (60 ÷ minutes between single IP requests)
For example, if you want to send 10,000 requests per day, and a single IP can only send 2 requests per minute, then you need 10,000/(60/2)=334 IPs

V. Guidelines and Special Reminders for Avoiding Pitfalls

1. Never buy a shared IP pool on the cheapIf you are in the business of account registration, ipipgo's exclusive IP is a bit expensive, but you can avoid being involved in the previous operation.
2. Attention to settingstime-out fuse mechanismIf an IP address fails 3 times in a row, it will be suspended for 2 hours.
3. Weekly update of the UA database and browser fingerprint database, do not let the risk control system to figure out the patterns
4. Say what is important three times:Do not use the server room IP!

Lastly, we recommend our own service: ipipgo recently went live!CAPTCHA Dedicated IP ChannelThe new user will get a free 5G traffic test package. Brothers engaged in automation projects can try, than self-built proxy pool to save a lot of effort.