CaptchaAI API Key Rotation: Multi-Key Management

Running all traffic through a single API key creates a single point of failure. If the key runs out of balance, hits rate limits, or gets deactivated, your entire pipeline stops. Key rotation distributes load across multiple keys and provides automatic failover.

Round-robin rotation

The simplest strategy — cycle through keys evenly:

Python

import itertools
import requests

API_KEYS = [
    "KEY_ACCOUNT_1",
    "KEY_ACCOUNT_2",
    "KEY_ACCOUNT_3",
]

key_cycle = itertools.cycle(API_KEYS)


def get_next_key():
    return next(key_cycle)


def solve_captcha(sitekey, page_url):
    api_key = get_next_key()
    resp = requests.post("https://ocr.captchaai.com/in.php", data={
        "key": api_key,
        "method": "userrecaptcha",
        "googlekey": sitekey,
        "pageurl": page_url,
        "json": "1",
    })
    data = resp.json()
    if data["status"] != 1:
        raise Exception(f"[{api_key[:8]}...] {data['request']}")

    print(f"Submitted with key {api_key[:8]}...")
    return data["request"], api_key


task_id, used_key = solve_captcha("6Le-SITEKEY", "https://example.com")

Weighted rotation with balance awareness

Route more traffic to keys with higher balances:

import random
import requests
import threading

SUBMIT_URL = "https://ocr.captchaai.com/in.php"
RESULT_URL = "https://ocr.captchaai.com/res.php"


class KeyRotator:
    def __init__(self, keys):
        self.keys = {k: {"balance": 0, "failures": 0, "disabled": False} for k in keys}
        self._lock = threading.Lock()
        self.refresh_balances()

    def refresh_balances(self):
        for key in self.keys:
            try:
                resp = requests.get(RESULT_URL, params={
                    "key": key, "action": "getbalance", "json": "1"
                }, timeout=10).json()
                if resp["status"] == 1:
                    self.keys[key]["balance"] = float(resp["request"])
                    self.keys[key]["disabled"] = False
                else:
                    self.keys[key]["disabled"] = True
            except Exception:
                self.keys[key]["disabled"] = True

    def get_key(self):
        with self._lock:
            available = {
                k: v for k, v in self.keys.items()
                if not v["disabled"] and v["balance"] > 0.01
            }
            if not available:
                raise Exception("No API keys with balance available")

            # Weighted random by balance
            keys = list(available.keys())
            weights = [available[k]["balance"] for k in keys]
            return random.choices(keys, weights=weights, k=1)[0]

    def report_failure(self, key, error_code):
        with self._lock:
            self.keys[key]["failures"] += 1
            if error_code in ("ERROR_WRONG_USER_KEY", "ERROR_KEY_DOES_NOT_EXIST",
                              "ERROR_ZERO_BALANCE", "ERROR_IP_NOT_ALLOWED"):
                self.keys[key]["disabled"] = True
                print(f"[rotator] Disabled key {key[:8]}...: {error_code}")

    def report_success(self, key, cost=0.003):
        with self._lock:
            self.keys[key]["balance"] -= cost
            self.keys[key]["failures"] = 0


rotator = KeyRotator(["KEY_1", "KEY_2", "KEY_3"])

# Usage
api_key = rotator.get_key()
# ... solve captcha ...
rotator.report_success(api_key)

Failover rotation

Try the next key when one fails:

Python

def solve_with_failover(sitekey, page_url, max_attempts=3):
    for attempt in range(max_attempts):
        api_key = rotator.get_key()
        try:
            resp = requests.post(SUBMIT_URL, data={
                "key": api_key,
                "method": "userrecaptcha",
                "googlekey": sitekey,
                "pageurl": page_url,
                "json": "1",
            }, timeout=15)
            data = resp.json()

            if data["status"] != 1:
                rotator.report_failure(api_key, data["request"])
                continue

            rotator.report_success(api_key)
            return data["request"], api_key

        except requests.RequestException:
            rotator.report_failure(api_key, "NETWORK_ERROR")
            continue

    raise Exception(f"All {max_attempts} keys failed")

JavaScript

const axios = require('axios');

class KeyRotator {
  constructor(keys) {
    this.keys = keys.map(k => ({ key: k, disabled: false, failures: 0 }));
    this.index = 0;
  }

  getKey() {
    const available = this.keys.filter(k => !k.disabled);
    if (available.length === 0) throw new Error('No API keys available');
    const entry = available[this.index % available.length];
    this.index++;
    return entry.key;
  }

  disable(key, reason) {
    const entry = this.keys.find(k => k.key === key);
    if (entry) {
      entry.disabled = true;
      console.log(`[rotator] Disabled ${key.substring(0, 8)}...: ${reason}`);
    }
  }
}

const rotator = new KeyRotator(['KEY_1', 'KEY_2', 'KEY_3']);

async function solveWithFailover(sitekey, pageurl, maxAttempts = 3) {
  for (let i = 0; i < maxAttempts; i++) {
    const apiKey = rotator.getKey();
    try {
      const resp = await axios.post('https://ocr.captchaai.com/in.php', null, {
        params: { key: apiKey, method: 'userrecaptcha', googlekey: sitekey, pageurl, json: 1 }
      });
      if (resp.data.status !== 1) {
        rotator.disable(apiKey, resp.data.request);
        continue;
      }
      return { taskId: resp.data.request, apiKey };
    } catch (err) {
      rotator.disable(apiKey, 'NETWORK_ERROR');
    }
  }
  throw new Error('All keys failed');
}

Loading keys from environment variables

Never hardcode API keys. Load from environment:

import os

API_KEYS = os.environ["CAPTCHAAI_KEYS"].split(",")
# Set: CAPTCHAAI_KEYS=key1,key2,key3
rotator = KeyRotator(API_KEYS)

const API_KEYS = process.env.CAPTCHAAI_KEYS.split(',');
const rotator = new KeyRotator(API_KEYS);

Scheduled balance refresh

For long-running processes, refresh balances periodically:

import threading

def periodic_refresh(rotator, interval=300):
    def refresh():
        while True:
            rotator.refresh_balances()
            for key, info in rotator.keys.items():
                print(f"  {key[:8]}...: ${info['balance']:.2f} "
                      f"{'(disabled)' if info['disabled'] else '(active)'}")
            threading.Event().wait(interval)

    t = threading.Thread(target=refresh, daemon=True)
    t.start()

periodic_refresh(rotator, interval=300)  # every 5 minutes

Troubleshooting

FAQ

How many API keys should I use?

Two keys provide basic failover. Three or more keys allow load distribution. For high-volume operations (1000+ solves/day), consider 3-5 keys.

Can I use keys from different CaptchaAI accounts?

Yes. Each key has its own balance and rate limits. The rotator treats them independently.

Scale your CAPTCHA solving with multi-key rotation

Get your API key at captchaai.com.

Related guides

• CaptchaAI IP Whitelisting and API Key Security
• Securing CaptchaAI Credentials in Environment Variables
• CaptchaAI Balance Check and Auto-Refill