Captcha: image to text

Any image-based captcha to text. 100% accuracy mode: solved until correct.

$15.00 / 1,000 POST /v1/query x402 · USDC on Base

Overview

Single endpoint, predictable JSON. Send POST /v1/query with the tool field set to captcha_image.

curl -X POST https://api.serp-base.com/v1/query \
  -H "Content-Type: application/json" \
  -d '{"tool": "captcha_image"}'

Parameters

Field	Type	Required	Description	Example
`image`	string (base64)	required	Captcha image, base64-encoded	`iVBORw0KGgo...`
`numeric`	int	optional	1 = digits only	`1`
`min_len`	int	optional	Minimum answer length (optional)	`4`
`max_len`	int	optional	Maximum answer length (optional)	`6`

Code examples

cURL

curl -X POST https://api.serp-base.com/v1/query \
  -H "Content-Type: application/json" \
  -d '{"tool": "captcha_image", "image": ""}'

Python

import requests

r = requests.post("https://api.serp-base.com/v1/query", json={
  "tool": "captcha_image",
  "image": ""
})
print(r.json()["data"])

JavaScript

const r = await fetch('https://api.serp-base.com/v1/query', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({
  "tool": "captcha_image",
  "image": ""
})
});
const { data } = await r.json();

PHP

$ch = curl_init('https://api.serp-base.com/v1/query');
curl_setopt_array($ch, [
  CURLOPT_POST => true,
  CURLOPT_HTTPHEADER => ['Content-Type: application/json'],
  CURLOPT_POSTFIELDS => '{"tool": "captcha_image", "image": ""}',
  CURLOPT_RETURNTRANSFER => true,
]);
$data = json_decode(curl_exec($ch), true);

Response

{
  "ok": true,
  "data": {
    "solution": "x4p9",
    "confidence": "high"
  }
}

Payment

Pay per request with USDC on Base via the x402 protocol. Gas is paid by the facilitator — you only need USDC in your wallet.

Network: Base mainnet (eip155:8453)
Asset: USDC
Price: $15.00 per 1,000 requests — charged only when data is returned
Test: Base Sepolia (eip155:84532) with free USDC from Circle faucet

No payment is taken when a service fails. We run the work first and settle afterwards.

Errors

Code	Meaning	Action
`402`	Payment required	Sign the payment and retry with `X-PAYMENT`
`400`	Bad parameters	Check required fields above
`422`	Data could not be produced	Nothing charged — retry later
`429`	Rate limited	Back off and retry
`503`	Tool temporarily unavailable	Retry later — nothing charged