# GTIN, UPC & EAN Barcode Validator (Check Digit) (`ultimatemc/gtin-barcode-validator`) Actor

Validate GTIN-8, UPC-A, UPC-E, EAN-13, GTIN-14 and ISBN codes before you upload a feed to Amazon, Google Merchant Center, Walmart or Shopify. Checks the check digit, lost leading zeros, scientific notation, GS1 prefix ranges, coupon and in-store codes, placeholders and duplicates.

- **URL**: https://apify.com/ultimatemc/gtin-barcode-validator.md
- **Developed by:** [Ultimate Foresight Inc](https://apify.com/ultimatemc) (community)
- **Categories:** E-commerce, Developer tools, Automation
- **Stats:** 2 total users, 1 monthly users, 100.0% runs succeeded, 0 bookmarks
- **User rating**: No ratings yet

## Pricing

from $0.50 / 1,000 results

This Actor is paid per event and usage. You are charged both the fixed price for specific events and for Apify platform usage.

Learn more: https://docs.apify.com/actors/running/actors-in-store.md#pay-per-event

## What's an Apify Actor?

An Actor is a serverless cloud program that runs on the Apify platform. It has two run modes.
In Batch mode, an Actor accepts a well-defined JSON input, performs an action which can take anything from a few seconds to a few hours,
and optionally produces a well-defined JSON output, datasets with results, or files in key-value store.
In Standby mode, an Actor provides a web server which can be used as a website, API, or an MCP server.

Apify vocabulary and the platform model are defined once, in the agent quickstart at https://apify.com/agents.md.

## How to integrate an Actor?

If asked about integration, you help developers integrate Actors into their projects.
You adapt to their stack and deliver integrations that are safe, well-documented, and production-ready.

Do not guess an integration path. Every one of them is in the agent quickstart at https://apify.com/agents.md: the Apify MCP server, Agent Skills with the Apify CLI, the JavaScript and Python clients, the REST API, and the account-free path for an agent with no human to sign in. It also carries the rule on stating cost before the first paid run.

For examples already wired to this Actor's own input schema, see the [API](#api) section below.

Each client library has reference documentation the quickstart does not restate: [JavaScript/TypeScript](https://docs.apify.com/api/client/js/docs.md) (`npm install apify-client`) and [Python](https://docs.apify.com/api/client/python/docs.md) (`pip install apify-client`).

# README

Check **GTIN, UPC, EAN and ISBN barcode numbers** before you upload a product feed to **Amazon, Google Merchant Center, Walmart, Shopify or eBay**. The **GTIN, UPC & EAN Barcode Validator** recalculates the **GS1 check digit**, finds **leading zeros lost in spreadsheets**, **scientific notation like 4.00638E+12**, **in-store and coupon codes**, **GS1 demo and unassigned prefixes**, **placeholder numbers** and **the same GTIN on different products**. It also converts every valid code to **GTIN-14, GTIN-13 and UPC-A**, expands **UPC-E** and turns **ISBN-10 into ISBN-13**. Click **Start** with the prefilled example to see it work.

> This is a structure check: check digit, length and GS1 prefix rules. A valid result does not prove GS1 issued the number or that it belongs to this product or brand; confirm ownership with Verified by GS1 or the brand owner. Every row carries this disclaimer.

### What does the GTIN, UPC & EAN Barcode Validator do?

- ✅ **Check digit**: the GS1 mod-10 check for GTIN-8, UPC-A (GTIN-12), EAN-13 and GTIN-14, and the mod-11 check for ISBN-10. Wrong check digits show the expected digit.
- ✅ **Spreadsheet damage**: 11-digit UPCs and 12-digit EANs that lost a leading zero, scientific notation (`4.00638E+12`) that destroyed the last digits, and letters or symbols mixed into the number.
- ✅ **Prefix meaning**: the GS1 prefix range and country or use (for example `003` UPC-A compatible, `978` books), with flags for in-store/restricted codes (`02`, `20-29`), coupon and receipt ranges, the `952` demo prefix and unassigned prefixes.
- ✅ **Placeholder numbers**: all-same digits, sequences like `123456789012` and other fill-ins that marketplaces reject.
- ✅ **Duplicates across your feed**: the same GTIN (after padding to 14 digits) on rows with different IDs or titles, which Amazon and Google treat as an error.
- ✅ **Conversions**: `gtin14`, `gtin13` and `upcA` for each valid code, UPC-E expanded to UPC-A, ISBN-10 converted to its 978 ISBN-13.
- ✅ Output per code: `status` (valid / valid with warnings / invalid), `type`, `checkDigitValid`, `expectedCheckDigit`, `prefix`, `prefixMeaning`, `issues` (`code`, `severity`, `message`, `sourceUrl`, `fixHint`), `notes`, `checkedAt` and a disclaimer.

### Who is it for?

- **Marketplace sellers and agencies** fixing feed errors before Amazon, Walmart or Google Merchant Center rejects listings.
- **Shopify and WooCommerce store owners** cleaning barcodes exported to spreadsheets.
- **Data and scraping teams** validating GTIN fields in scraped product data before matching products across sites.
- **Price comparison and catalog sites** that join products on GTIN and need clean keys.

### How to validate GTIN and UPC codes

1. Click **Start** with the prefilled example (seven codes with common feed mistakes).
2. Paste your codes into **Codes only**, or use **Products** with `gtin` (or `upc`, `ean`, `barcode`, `isbn`) plus optional `id`, `title` and `url` to get duplicate checks by product.
3. Or enter a **Dataset ID** from a Shopify, Amazon, Walmart or other product scraper. Common fields are found automatically; use **Field map** with dotted paths (for example `variants.0.barcode`) for nested ones.
4. Turn on **Only save rows with findings** to skip clean codes; you only pay for saved rows.
5. Export the results as CSV, Excel or JSON, or fetch them through the API.

### Input example

This is the prefilled input:

```json
{
  "products": [
    {
      "id": "SKU-1",
      "title": "Example valid UPC-A",
      "gtin": "036000291452"
    },
    {
      "id": "SKU-2",
      "title": "Example wrong check digit",
      "gtin": "036000291453"
    },
    {
      "id": "SKU-3",
      "title": "Example lost leading zero (11 digits)",
      "gtin": "36000291452"
    },
    {
      "id": "SKU-4",
      "title": "Example spreadsheet scientific notation",
      "gtin": "4.00638E+12"
    },
    {
      "id": "SKU-5",
      "title": "Example in-store (restricted) code",
      "gtin": "2012345678903"
    },
    {
      "id": "SKU-6",
      "title": "Example duplicate of SKU-1",
      "gtin": "0036000291452"
    },
    {
      "id": "SKU-7",
      "title": "Example ISBN-10",
      "gtin": "0-306-40615-2"
    }
  ]
}
```

Dataset mode:

```json
{"datasetId": "YOUR_DATASET_ID", "fieldMap": {"gtin": "variants.0.barcode", "id": "sku", "title": "title"}, "onlyFlagged": true, "maxItems": 10000}
```

### Output example

Real output from a run of the prefilled input on 2026-10-30 (long finding lists are shortened here; the run returns all of them):

```json
[
  {
    "itemNo": 1,
    "productId": "SKU-1",
    "title": "Example valid UPC-A",
    "url": null,
    "input": "036000291452",
    "digits": "036000291452",
    "type": "UPC-A (GTIN-12)",
    "checkDigitValid": true,
    "expectedCheckDigit": "2",
    "gtin14": "00036000291452",
    "gtin13": "0036000291452",
    "upcA": "036000291452",
    "prefix": "003",
    "prefixMeaning": "UPC-A compatible - United States",
    "status": "valid with warnings",
    "issues": [
      {
        "code": "duplicate_gtin_in_run",
        "severity": "medium",
        "message": "The same GTIN appears on 3 rows with different IDs or titles (also on: SKU-3, SKU-6).",
        "sourceUrl": "https://sellercentral.amazon.com/help/hub/reference/external/G200317470",
        "fixHint": "Each distinct product (size, color, pack count) needs its own GTIN; variants can't share one."
      }
    ],
    "notes": [],
    "issueCount": 1,
    "checkedAt": "2026-10-30T18:52:05+00:00",
    "disclaimer": "Structure check only: GS1 check digit, length and prefix rules. A valid result does not..."
  },
  {
    "itemNo": 2,
    "productId": "SKU-2",
    "title": "Example wrong check digit",
    "url": null,
    "input": "036000291453",
    "digits": "036000291453",
    "type": "UPC-A (GTIN-12)",
    "checkDigitValid": false,
    "expectedCheckDigit": "2",
    "gtin14": "00036000291453",
    "gtin13": "0036000291453",
    "upcA": "036000291453",
    "prefix": "003",
    "prefixMeaning": "UPC-A compatible - United States",
    "status": "invalid",
    "issues": [
      {
        "code": "bad_check_digit",
        "severity": "high",
        "message": "Check digit is 3, but GS1's formula gives 2.",
        "sourceUrl": "https://www.gs1.org/services/how-calculate-check-digit-manually",
        "fixHint": "Usually a typo or a copied/made-up number. Take the code from the physical barcode or the brand owner."
      }
    ],
    "notes": [],
    "issueCount": 1,
    "checkedAt": "2026-10-30T18:52:05+00:00",
    "disclaimer": "Structure check only: GS1 check digit, length and prefix rules. A valid result does not..."
  },
  {
    "itemNo": 3,
    "productId": "SKU-3",
    "title": "Example lost leading zero (11 digits)",
    "url": null,
    "input": "36000291452",
    "digits": "36000291452",
    "type": "UPC-A (GTIN-12), leading zero missing",
    "checkDigitValid": true,
    "expectedCheckDigit": "2",
    "gtin14": "00036000291452",
    "gtin13": "0036000291452",
    "upcA": "036000291452",
    "prefix": "003",
    "prefixMeaning": "UPC-A compatible - United States",
    "status": "valid with warnings",
    "issues": [
      {
        "code": "leading_zero_lost",
        "severity": "medium",
        "message": "11 digits: this looks like a UPC-A whose leading 0 was dropped (with the 0 restored, the check digit is valid).",
        "sourceUrl": "https://support.google.com/merchants/answer/6324461",
        "fixHint": "Store it as text with the leading zero: 036000291452."
      },
      {
        "code": "duplicate_gtin_in_run",
        "severity": "medium",
        "message": "The same GTIN appears on 3 rows with different IDs or titles (also on: SKU-1, SKU-6).",
        "sourceUrl": "https://sellercentral.amazon.com/help/hub/reference/external/G200317470",
        "fixHint": "Each distinct product (size, color, pack count) needs its own GTIN; variants can't share one."
      }
    ],
    "notes": [],
    "issueCount": 2,
    "checkedAt": "2026-10-30T18:52:05+00:00",
    "disclaimer": "Structure check only: GS1 check digit, length and prefix rules. A valid result does not..."
  },
  {
    "itemNo": 4,
    "productId": "SKU-4",
    "title": "Example spreadsheet scientific notation",
    "url": null,
    "input": "4.00638E+12",
    "digits": null,
    "type": null,
    "checkDigitValid": null,
    "expectedCheckDigit": null,
    "gtin14": null,
    "gtin13": null,
    "upcA": null,
    "prefix": null,
    "prefixMeaning": null,
    "status": "invalid",
    "issues": [
      {
        "code": "spreadsheet_scientific_notation",
        "severity": "high",
        "message": "'4.00638E+12' is in scientific notation, so the spreadsheet has already rounded away the last digits.",
        "sourceUrl": "https://support.google.com/merchants/answer/6324461",
        "fixHint": "Re-export the column formatted as text; the original digits can't be recovered from this value."
      }
    ],
    "notes": [],
    "issueCount": 1,
    "checkedAt": "2026-10-30T18:52:05+00:00",
    "disclaimer": "Structure check only: GS1 check digit, length and prefix rules. A valid result does not..."
  },
  {
    "itemNo": 5,
    "productId": "SKU-5",
    "title": "Example in-store (restricted) code",
    "url": null,
    "input": "2012345678903",
    "digits": "2012345678903",
    "type": "EAN-13 (GTIN-13)",
    "checkDigitValid": true,
    "expectedCheckDigit": "3",
    "gtin14": "02012345678903",
    "gtin13": "2012345678903",
    "upcA": null,
    "prefix": "201",
    "prefixMeaning": "Used to issue GS1 restricted circulation number within a geographic region",
    "status": "valid with warnings",
    "issues": [
      {
        "code": "restricted_circulation",
        "severity": "medium",
        "message": "Prefix 201 is for restricted circulation (in-store or internal numbers), not a global product ID.",
        "sourceUrl": "https://www.gs1.org/standards/id-keys/company-prefix",
        "fixHint": "Marketplaces expect the brand owner's GTIN; store-issued codes are often rejected."
      }
    ],
    "notes": [],
    "issueCount": 1,
    "checkedAt": "2026-10-30T18:52:05+00:00",
    "disclaimer": "Structure check only: GS1 check digit, length and prefix rules. A valid result does not..."
  },
  {
    "itemNo": 6,
    "productId": "SKU-6",
    "title": "Example duplicate of SKU-1",
    "url": null,
    "input": "0036000291452",
    "digits": "0036000291452",
    "type": "EAN-13 (GTIN-13)",
    "checkDigitValid": true,
    "expectedCheckDigit": "2",
    "gtin14": "00036000291452",
    "gtin13": "0036000291452",
    "upcA": "036000291452",
    "prefix": "003",
    "prefixMeaning": "UPC-A compatible - United States",
    "status": "valid with warnings",
    "issues": [
      {
        "code": "duplicate_gtin_in_run",
        "severity": "medium",
        "message": "The same GTIN appears on 3 rows with different IDs or titles (also on: SKU-1, SKU-3).",
        "sourceUrl": "https://sellercentral.amazon.com/help/hub/reference/external/G200317470",
        "fixHint": "Each distinct product (size, color, pack count) needs its own GTIN; variants can't share one."
      }
    ],
    "notes": [],
    "issueCount": 1,
    "checkedAt": "2026-10-30T18:52:05+00:00",
    "disclaimer": "Structure check only: GS1 check digit, length and prefix rules. A valid result does not..."
  },
  {
    "itemNo": 7,
    "productId": "SKU-7",
    "title": "Example ISBN-10",
    "url": null,
    "input": "0-306-40615-2",
    "digits": "0306406152",
    "type": "ISBN-10",
    "checkDigitValid": true,
    "expectedCheckDigit": null,
    "gtin14": "09780306406157",
    "gtin13": "9780306406157",
    "upcA": null,
    "prefix": "978",
    "prefixMeaning": "Book (ISBN converted to ISBN-13 / EAN-13)",
    "status": "valid",
    "issues": [],
    "notes": [
      "Converted ISBN-10 to its 978 ISBN-13, which is the barcode number marketplaces expect."
    ],
    "issueCount": 0,
    "checkedAt": "2026-10-30T18:52:05+00:00",
    "disclaimer": "Structure check only: GS1 check digit, length and prefix rules. A valid result does not..."
  }
]
```

### How much does it cost to validate barcodes?

This Actor uses pay-per-event pricing: **$0.0005 per code saved** plus a **$0.00005 start fee per run**, plus small platform usage paid by you (a few hundredths of a cent for small runs). That's about **$0.50 for 1,000 codes** and **$5 for 10,000 codes** plus usage. With **Only save rows with findings** on, valid codes aren't saved or charged. You can set a maximum cost per run in the run options.

### Use it through the API, integrations or AI agents

- Run it and get results in one call: `https://api.apify.com/v2/acts/ultimatemc~gtin-barcode-validator/run-sync-get-dataset-items`
- Use it from AI agents through the Apify MCP server: `https://mcp.apify.com?tools=ultimatemc/gtin-barcode-validator`
- Schedule it after a daily scraper run, send flagged rows to Slack or email with webhooks, or connect it to Make, Zapier, n8n or Google Sheets.
- Chain it after a product scraper by passing the scraper's dataset ID.

### How it works

Validation is fully deterministic and runs offline: the GS1 check digit formula, the length rules of the GS1 General Specifications and a built-in GS1 prefix table, checked on 2026-10-30. No barcode database is queried, so it's fast and cheap, but it can't tell you who owns a number. Duplicates are found by padding every valid code to GTIN-14 and comparing rows in the same run.

Sources:

- [GS1: How to calculate a check digit manually](https://www.gs1.org/services/how-calculate-check-digit-manually)
- [GS1 General Specifications](https://www.gs1.org/standards/barcodes-epcrfid-id-keys/gs1-general-specifications)
- [GS1 Company Prefix](https://www.gs1.org/standards/id-keys/company-prefix)
- [Verified by GS1](https://www.gs1.org/services/verified-by-gs1)
- [Amazon Seller Central: Product UPCs and GTINs](https://sellercentral.amazon.com/help/hub/reference/external/G200317470)
- [Google Merchant Center: GTIN](https://support.google.com/merchants/answer/6324461)
- [International ISBN Agency: What is an ISBN?](https://www.isbn-international.org/content/what-isbn/10)

### FAQ

#### Does "valid" mean the barcode is real and mine?

No. It means the number has the right length, check digit and prefix structure. Marketplaces also check GS1 ownership; use Verified by GS1 to confirm who licensed a number.

#### Why is my 11-digit UPC flagged?

Spreadsheets often drop the leading zero of a UPC-A. If adding the zero gives a valid check digit, the row is marked `leading_zero_lost` and the corrected code is shown.

#### Can it fix scientific notation like 4.00638E+12?

No. That format has already lost the last digits, so the original number can't be recovered. Re-export the column as text.

#### Does it look up product names?

No. It doesn't call any barcode database, which keeps it fast and costs at $0.0005 per code.

#### Is it AI?

No. It's a fixed set of GS1 rules, so results are repeatable.

### Limitations

- Ownership isn't checked; a correctly formed number can still belong to someone else.
- The GS1 prefix table is built in and reflects GS1 published ranges as of 2026-10-30.
- Duplicates are only detected within one run.
- Codes damaged by scientific notation can't be repaired.

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- [Unit Price Checker for Grocery & Retail Listings](https://apify.com/ultimatemc/unit-price-checker): parses pack sizes, recomputes the price per kg, litre or item, and flags missing or wrong unit prices in grocery and retail data.
- [Made in USA Claim Checker for Product Listings](https://apify.com/ultimatemc/made-in-usa-claim-checker): flags unqualified 'Made in USA' claims next to imported or foreign-origin details under the FTC rule (16 CFR 323), with sources per finding.
- [Subscription Auto-Renewal Disclosure Checker](https://apify.com/ultimatemc/auto-renewal-disclosure-checker): checks subscription and free-trial offer text for missing renewal, price, billing period and cancellation disclosures under California law and FTC ROSCA.
- [Email CAN-SPAM Checker & Unsubscribe Header Test](https://apify.com/ultimatemc/email-can-spam-checker): pre-checks marketing emails for missing unsubscribe links or postal address, misleading subjects and Google/Yahoo one-click unsubscribe headers.

Found a wrong result? Open an issue on the **Issues** tab with the code and what you expected, and we'll review the rule.

# Actor input Schema

## `products` (type: `array`):

Array of objects with "gtin" (or upc, ean, barcode, isbn) and optional "id", "title" and "url". The prefilled example mixes valid codes with common feed mistakes; replace it with your own.

## `codes` (type: `array`):

One GTIN, UPC, EAN or ISBN per entry. Hyphens and spaces are removed.

## `datasetId` (type: `string`):

Apify dataset with products, for example the output of a Shopify, Amazon, Walmart or Idealo scraper. Common fields (gtin, gtin13, upc, ean, barcode, isbn, sku, id, title, url) are detected automatically; override them with Field map.

## `fieldMap` (type: `object`):

Override field names; dotted paths work for nested fields. Example: {"gtin": "variants.0.barcode", "id": "sku", "title": "name"}.

## `onlyFlagged` (type: `boolean`):

Skip codes with status valid (you are only charged for saved rows).

## `maxItems` (type: `integer`):

Maximum number of codes to check in this run.

## Actor input object example

```json
{
  "products": [
    {
      "id": "SKU-1",
      "title": "Example valid UPC-A",
      "gtin": "036000291452"
    },
    {
      "id": "SKU-2",
      "title": "Example wrong check digit",
      "gtin": "036000291453"
    },
    {
      "id": "SKU-3",
      "title": "Example lost leading zero (11 digits)",
      "gtin": "36000291452"
    },
    {
      "id": "SKU-4",
      "title": "Example spreadsheet scientific notation",
      "gtin": "4.00638E+12"
    },
    {
      "id": "SKU-5",
      "title": "Example in-store (restricted) code",
      "gtin": "2012345678903"
    },
    {
      "id": "SKU-6",
      "title": "Example duplicate of SKU-1",
      "gtin": "0036000291452"
    },
    {
      "id": "SKU-7",
      "title": "Example ISBN-10",
      "gtin": "0-306-40615-2"
    }
  ],
  "onlyFlagged": false,
  "maxItems": 10000
}
```

# Actor output Schema

## `results` (type: `string`):

No description

# API

You can run this Actor programmatically using our API. Below are code examples in JavaScript, Python, and CLI, as well as the OpenAPI specification and MCP server setup.

## JavaScript example

```javascript
import { ApifyClient } from 'apify-client';

// Initialize the ApifyClient with your Apify API token
// Replace the '<YOUR_API_TOKEN>' with your token
const client = new ApifyClient({
    token: '<YOUR_API_TOKEN>',
});

// Prepare Actor input
const input = {
    "products": [
        {
            "id": "SKU-1",
            "title": "Example valid UPC-A",
            "gtin": "036000291452"
        },
        {
            "id": "SKU-2",
            "title": "Example wrong check digit",
            "gtin": "036000291453"
        },
        {
            "id": "SKU-3",
            "title": "Example lost leading zero (11 digits)",
            "gtin": "36000291452"
        },
        {
            "id": "SKU-4",
            "title": "Example spreadsheet scientific notation",
            "gtin": "4.00638E+12"
        },
        {
            "id": "SKU-5",
            "title": "Example in-store (restricted) code",
            "gtin": "2012345678903"
        },
        {
            "id": "SKU-6",
            "title": "Example duplicate of SKU-1",
            "gtin": "0036000291452"
        },
        {
            "id": "SKU-7",
            "title": "Example ISBN-10",
            "gtin": "0-306-40615-2"
        }
    ]
};

// Run the Actor and wait for it to finish
const run = await client.actor("ultimatemc/gtin-barcode-validator").call(input);

// Fetch and print Actor results from the run's dataset (if any)
console.log('Results from dataset');
console.log(`💾 Check your data here: https://console.apify.com/storage/datasets/${run.defaultDatasetId}`);
const { items } = await client.dataset(run.defaultDatasetId).listItems();
items.forEach((item) => {
    console.dir(item);
});

// 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/js/docs

```

## Python example

```python
from apify_client import ApifyClient

# Initialize the ApifyClient with your Apify API token
# Replace '<YOUR_API_TOKEN>' with your token.
client = ApifyClient("<YOUR_API_TOKEN>")

# Prepare the Actor input
run_input = { "products": [
        {
            "id": "SKU-1",
            "title": "Example valid UPC-A",
            "gtin": "036000291452",
        },
        {
            "id": "SKU-2",
            "title": "Example wrong check digit",
            "gtin": "036000291453",
        },
        {
            "id": "SKU-3",
            "title": "Example lost leading zero (11 digits)",
            "gtin": "36000291452",
        },
        {
            "id": "SKU-4",
            "title": "Example spreadsheet scientific notation",
            "gtin": "4.00638E+12",
        },
        {
            "id": "SKU-5",
            "title": "Example in-store (restricted) code",
            "gtin": "2012345678903",
        },
        {
            "id": "SKU-6",
            "title": "Example duplicate of SKU-1",
            "gtin": "0036000291452",
        },
        {
            "id": "SKU-7",
            "title": "Example ISBN-10",
            "gtin": "0-306-40615-2",
        },
    ] }

# Run the Actor and wait for it to finish
run = client.actor("ultimatemc/gtin-barcode-validator").call(run_input=run_input)

# Fetch and print Actor results from the run's dataset (if there are any)
print(f"💾 Check your data here: https://console.apify.com/storage/datasets/{run.default_dataset_id}")
for item in client.dataset(run.default_dataset_id).iterate_items():
    print(item)

# 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/python/docs/quick-start

```

## CLI example

```bash
echo '{
  "products": [
    {
      "id": "SKU-1",
      "title": "Example valid UPC-A",
      "gtin": "036000291452"
    },
    {
      "id": "SKU-2",
      "title": "Example wrong check digit",
      "gtin": "036000291453"
    },
    {
      "id": "SKU-3",
      "title": "Example lost leading zero (11 digits)",
      "gtin": "36000291452"
    },
    {
      "id": "SKU-4",
      "title": "Example spreadsheet scientific notation",
      "gtin": "4.00638E+12"
    },
    {
      "id": "SKU-5",
      "title": "Example in-store (restricted) code",
      "gtin": "2012345678903"
    },
    {
      "id": "SKU-6",
      "title": "Example duplicate of SKU-1",
      "gtin": "0036000291452"
    },
    {
      "id": "SKU-7",
      "title": "Example ISBN-10",
      "gtin": "0-306-40615-2"
    }
  ]
}' |
apify call ultimatemc/gtin-barcode-validator --silent --output-dataset

```

## MCP server setup

```json
{
    "mcpServers": {
        "apify": {
            "type": "http",
            "url": "https://mcp.apify.com/?tools=fetch-actor-details,ultimatemc/gtin-barcode-validator"
        }
    }
}
```

The hosted server signs you in with OAuth on first connect, so no API token belongs in this config. Clients without OAuth support can send an `Authorization: Bearer <APIFY_API_TOKEN>` header instead, using a token from API & Integrations in Apify Console (https://console.apify.com/settings/integrations).

## OpenAPI specification

Download the OpenAPI definition: https://api.apify.com/v2/actors/CP8CwBt8Ej1RuofH5/builds/kVpw6o8LRSyi2AdNa/openapi.json