# GTIN/EAN Barcode Check Digit Validator

> GTIN/EAN Barcode Check Digit Validator is a paid API for AI agents from checkdigit.openverbs.com, paid per call via x402, $0.002/call, status unknown (last checked 2026-09-15).

Validates EAN-8, UPC-A (12-digit), EAN-13, or GTIN-14 barcode numbers using the standard mod-10 check digit algorithm.

## Facts

- Endpoint: POST https://checkdigit.openverbs.com/v1/ean
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/gtin-ean-barcode-check-digit-validator-7ad1f398
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_IlAbg95IUYjyiXnQlfBQa

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-barcode-check-digit-validator-7ad1f398 -d '<json body>'
```

Example prompt: Can you check whether the barcode number 0614141999996 is a valid EAN-13? I want to make sure it passes the mod-10 check digit before I add it to my product catalog.

## When to prefer this

Choose this endpoint when you need fast, lightweight validation of a GTIN-family barcode (EAN-8, UPC-A, EAN-13, GTIN-14) using the standard mod-10 check digit algorithm. It is ideal for pre-validation in e-commerce product onboarding, inventory management, and supply chain workflows. Prefer it over full barcode lookup services when you only need to confirm structural validity, not product metadata. Sibling endpoints on the same platform handle ISBN, IMEI, Luhn (credit card), and ABA routing number validation separately.

## Known failure modes

- Invalid length: number is not 8, 12, 13, or 14 digits after stripping spaces/hyphens
- Non-numeric characters that are not spaces or hyphens cause a rejection
- Check digit mismatch: number fails mod-10 validation and is flagged as invalid
- Empty or missing 'number' field returns a schema validation error
- Network timeout or service unavailability returns a 5xx error

## How this service works

Validate a GTIN barcode number — EAN-8, UPC-A (12), EAN-13 or GTIN-14 — by the standard mod-10 check digit. Length selects the scheme.

## Output

Returns a pass/fail validation result indicating whether the provided barcode number has a correct mod-10 check digit. The length of the input determines which GTIN scheme (EAN-8, UPC-A, EAN-13, or GTIN-14) is applied. Spaces and hyphens in the input are tolerated.

## Request schema (JSON Schema)

```json
{
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "type": "object",
 "properties": {
  "input": {
   "type": "object",
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "type": "string",
     "enum": [
      "POST"
     ]
    },
    "bodyType": {
     "type": "string",
     "enum": [
      "json",
      "form-data",
      "text"
     ]
    },
    "body": {
     "type": "object",
     "properties": {
      "number": {
       "type": "string",
       "minLength": 1,
       "maxLength": 32,
       "description": "8, 12, 13 or 14 digit GTIN (spaces/hyphens allowed)."
      }
     },
     "required": [
      "number"
     ],
     "additionalProperties": false
    }
   },
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "additionalProperties": false
  }
 },
 "required": [
  "input"
 ]
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/gtin-ean-barcode-check-digit-validator-7ad1f398/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from checkdigit.openverbs.com](https://www.zero.xyz/host/checkdigit.openverbs.com/llms.txt)