# GTIN / EAN / UPC Barcode Check-Digit Validator

> GTIN / EAN / UPC Barcode Check-Digit Validator is a paid API for AI agents from api.aventtech.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-09).

Validates GTIN-8, GTIN-12 (UPC-A), GTIN-13 (EAN-13), and GTIN-14 barcodes using GS1 MOD-10 check-digit algorithm and identifies the barcode type.

## Facts

- Endpoint: GET https://api.aventtech.com/validate/gtin?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-09
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/gtin-ean-upc-barcode-check-digit-validator-061f0eed
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_vOitUrLOEvkClSjKNpnSR

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability gtin-ean-upc-barcode-check-digit-validator-061f0eed
```

Example prompt: Can you check if the barcode 5901234123457 is a valid GTIN and tell me what type it is?

## When to prefer this

Use this endpoint when you need lightweight, fast, purely structural GS1 MOD-10 check-digit validation of a barcode without needing product database lookup. It is ideal for input sanitization, data entry validation, or pre-processing barcodes before querying a product database. Prefer this over payment-card or IBAN validators — those are sibling endpoints on the same host for different number formats.

## Known failure modes

- Non-numeric characters in the GTIN input cause a validation error
- GTIN length not matching any of 8, 12, 13, or 14 digits returns an invalid format error
- Empty or missing gtin query parameter returns a 400 bad request
- Network timeout or service unavailability returns a 5xx error

## How this service works

GTIN / EAN / UPC barcode check-digit validation (GS1 mod-10) for GTIN-8/12/13/14 with type identification.

## Output

Returns whether the GTIN passes GS1 MOD-10 check-digit validation, the barcode type (GTIN-8, GTIN-12/UPC-A, GTIN-13/EAN-13, or GTIN-14), and likely whether the check digit itself is correct.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "gtin"
     ],
     "properties": {
      "gtin": {
       "type": "string",
       "description": "8, 12, 13 or 14 digit barcode number"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "kind": "GTIN-13/EAN-13",
  "valid": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/gtin-ean-upc-barcode-check-digit-validator-061f0eed/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.aventtech.com](https://www.zero.xyz/host/api.aventtech.com/llms.txt)