Barcode / QR decode

Decode a barcode or QR code from an image. Send a base64 PNG or JPEG (or a data: URL); returns the decoded text and the symbology. Reads QR, DataMatrix, and 1D barcodes (EAN/UPC/Code39/Code128/ITF/Codabar). Deterministic, no network, no model.

Input

Field	Type	Description
image *	string	base64-encoded PNG or JPEG, optionally a data: URL

Example output

{
  "found": true,
  "format": "QR_CODE",
  "text": "AGENT402",
  "decoder": "zxing"
}

Try it - see the 402 challenge (free)

curl -i -X POST https://agent402.tools/api/barcode-decode \
  -H "Content-Type: application/json" \
  -d '{"image":"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"}'

The response is HTTP 402 Payment Required with exact payment requirements. Any x402 v2 client pays automatically and retries:

Paid call (JavaScript agent)

import { wrapFetchWithPayment } from "@x402/fetch";
import { x402Client } from "@x402/core/client";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

const client = new x402Client();
registerExactEvmScheme(client, { signer: privateKeyToAccount(KEY) });
const payFetch = wrapFetchWithPayment(fetch, client);

const res = await payFetch("https://agent402.tools/api/barcode-decode", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({
    "image": "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"
  }),
});

No wallet? Pay with compute

This is a pure-CPU tool, so an agent without a wallet can pay with proof-of-work instead of USDC: fetch a challenge, solve the sha256 puzzle (16 leading zero bits - a fraction of a second of CPU, no money, no AI tokens), and resend with the X-Pow-Solution header.

import { createHash } from "node:crypto";
const lz = (b) => { let t = 0; for (const x of b) { if (!x) { t += 8; continue; } t += Math.clz32(x) - 24; break; } return t; };
const c = await (await fetch("https://agent402.tools/api/pow/challenge?slug=barcode-decode")).json();
let n = 0;
while (lz(createHash("sha256").update(c.challenge + ":" + n).digest()) < c.difficulty) n++;
await fetch("https://agent402.tools/api/barcode-decode", { method: "POST", headers: { "X-Pow-Solution": c.token + ":" + n, "Content-Type": "application/json" }, body: JSON.stringify({"image":"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"}) });

Part of these workflows

This tool is one step in 2 curated multi-tool workflows - agents can fetch the whole sequence as an MCP prompt or call https://agent402.tools/api/skill-packs/{slug}/prompt.

• Document intelligence - Turn any PDF or image URL into structured data - metadata, extracted text, sliced page ranges, OCR for scanned docs, decoded barcodes / QR codes - without falling back to a vision LLM guess. Built for the messy 30% of documents where pdf-to-markdown alone returns nothing useful.
• Uploaded-media normalize - The 'user uploaded a thing, normalize it before storing' workflow. Probe the file (image or audio/video) with media-info, decode any embedded barcodes/QRs, resize and thumbnail the image, convert it to a web-friendly format, and normalize audio loudness to broadcast standard. Six tools, one canonical normalize-on-upload pipeline that turns arbitrary user uploads into predictable storage artifacts.

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