API reference

createTask

Submit a CAPTCHA to solve and receive a task id.

Creates a solve task and returns immediately. The response carries a taskId you then poll with getTaskResult. The task price is debited from your wallet here, and credited back automatically if the task ends in failure.

POST https://api.captchapi.com/createTask
content-type: application/json

Request fields

Field	Type	Required	Description
`clientKey`	string	yes	Your API key.
`task.type`	string	yes	One of the supported task types. Case-insensitive.
`task.websiteURL`	string	yes	The full URL of the page carrying the CAPTCHA, including scheme.
`task.websiteKey`	string	usually	The widget sitekey. Not needed for Cloudflare full-page challenge tasks, which have no sitekey.
`task.pageAction`	string	no	reCAPTCHA v3 action name. Send the same value the site uses, or the score will be wrong.
`task.isInvisible`	boolean	no	Set for invisible reCAPTCHA v2 and invisible hCaptcha widgets.
`task.data`	string	no	Extra payload some widgets require: the FunCaptcha blob, or hCaptcha rqdata.
`task.funcaptchaApiJSSubdomain`	string	no	Custom Arkose api.js subdomain when the target uses one.
`task.userAgent`	string	no	Exact User-Agent to solve with. A Firefox UA is honoured by a real Gecko engine, not a spoofed header, which adds a few seconds.
`task.proxyType`	string	with proxy	http, https, socks4 or socks5.
`task.proxyAddress`	string	with proxy	Proxy host or IP. Must be reachable from our egress.
`task.proxyPort`	number	with proxy	Proxy port.
`task.proxyLogin`	string	no	Proxy username, if the proxy authenticates.
`task.proxyPassword`	string	no	Proxy password, if the proxy authenticates.

Examples

reCAPTCHA v3 with a page action

{
  "clientKey": "YOUR_API_KEY",
  "task": {
    "type": "ReCaptchaV3TokenProxyLess",
    "websiteURL": "https://example.com/checkout",
    "websiteKey": "6LcR_okUAAAAAPYrPe-HK_0RULO1aZM15ENyM-Mf",
    "pageAction": "checkout"
  }
}

Turnstile through your own proxy, with an exact User-Agent

{
  "clientKey": "YOUR_API_KEY",
  "task": {
    "type": "TurnstileToken",
    "websiteURL": "https://example.com/login",
    "websiteKey": "0x4AAAAAAADnPIDROrmt1Wwj",
    "proxyType": "http",
    "proxyAddress": "203.0.113.10",
    "proxyPort": 8080,
    "proxyLogin": "user",
    "proxyPassword": "pass",
    "userAgent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/141.0.0.0 Safari/537.36"
  }
}

Cloudflare full-page challenge — no sitekey

{
  "clientKey": "YOUR_API_KEY",
  "task": {
    "type": "CloudflareChallengeCookie",
    "websiteURL": "https://example.com/protected"
  }
}

Response

Accepted

{
  "errorId": 0,
  "taskId": "9f2c4b1e-6f0a-4d5e-b6c1-2f7a9d3e51c8"
}

Rejected — HTTP is still 200

{
  "errorId": 1,
  "errorCode": "ERROR_ZERO_BALANCE",
  "errorDescription": "Your wallet balance is 0.00 USD. Top up to create tasks."
}

The debit happens here, before the solve. That is what lets us answer in milliseconds instead of holding your request open during a credit check. Every failed task is credited back with the same task id, so the two movements always pair up in your wallet history.