GTIN / EAN Barcode Validator
GTIN barcode validator: validate and convert GS1 identifiers: GTIN-8, GTIN-12 (UPC-A), GTIN-13 (EAN-13), GTIN-14, GLN and SSCC. Returns the check-digit verdict, the computed correct check digit, the GTIN-14 form with its indicator digit, and conversion between GTIN-8, -12, -13 and -14. No company-prefix split is returned: GS1's prefix-length table is no longer public data. Also computes a missing check digit from a partial code. Structure only, no product database.
Offering
- Provider
- api.duoleads.com
- Method
- GET
- Offering type
- Api Endpoint
- Transport type
- http
- Category
- General Utilities
- Delivery
- Not provided
- Pricing model
- Not provided
- x402 version
- 2
Endpoint context
- URL
https://api.duoleads.com/v1/id/gs1- MIME type
- application/json
- First seen
- 2026-10-16T01:50:38.788Z
- Last seen
- Tags
- gtin, barcode, ean, identifiers, Validation
Payment pricing
x402 payment terms are the authoritative price for calling this endpoint.
- Payment option 1
- 0.05 USDC
Atomic price: 50000 · Network: eip155:8453 · Asset: USDC · Scheme: exact
Raw x402 terms
[
{
"scheme": "exact",
"network": "eip155:8453",
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"amount": "50000",
"payTo": "0xCD673f7e1daD254347AEab6be0DEFe8b9C6b3A39"
}
]Observed health
- Status
- Healthy
- Latest latency
- 1161 ms
- Average latency
- 760 ms
- HTTP status
- 402
- Last checked
- Reachability
- 100% over 14 checks
Latency is measured to the first response headers. A reachable result does not verify response accuracy or merchant identity.
Input schema
{
"type": "object",
"properties": {
"type": {
"type": "string",
"const": "http"
},
"method": {
"type": "string",
"enum": [
"GET"
]
},
"queryParams": {
"type": "object",
"properties": {
"op": {
"type": "string",
"description": "validate (default), checkdigit (compute the missing final digit) or convert.",
"enum": [
"validate",
"checkdigit",
"convert"
],
"maxLength": 64,
"default": "validate"
},
"value": {
"type": "string",
"description": "GS1 code, digits with optional spaces or hyphens. For op=checkdigit, omit the final digit.",
"maxLength": 32
},
"to": {
"type": "string",
"description": "Target format. Required when op=convert.",
"enum": [
"gtin8",
"gtin12",
"gtin13",
"gtin14"
],
"maxLength": 64
}
},
"required": [
"value"
]
}
},
"required": [
"type",
"method"
],
"additionalProperties": false
}Output schema
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"method": {
"enum": [
"GET"
],
"type": "string"
},
"queryParams": {
"properties": {
"op": {
"default": "validate",
"description": "validate (default), checkdigit (compute the missing final digit) or convert.",
"enum": [
"validate",
"checkdigit",
"convert"
],
"maxLength": 64,
"type": "string"
},
"to": {
"description": "Target format. Required when op=convert.",
"enum": [
"gtin8",
"gtin12",
"gtin13",
"gtin14"
],
"maxLength": 64,
"type": "string"
},
"value": {
"description": "GS1 code, digits with optional spaces or hyphens. For op=checkdigit, omit the final digit.",
"maxLength": 32,
"type": "string"
}
},
"required": [
"value"
],
"type": "object"
},
"type": {
"const": "http",
"type": "string"
}
},
"required": [
"type",
"method"
],
"type": "object"
},
"output": {
"properties": {
"example": {
"properties": {
"data": {
"properties": {
"also_valid_as": {
"items": {
"type": "string"
},
"type": "array"
},
"check_digit": {
"type": [
"string",
"null"
]
},
"check_digit_ok": {
"type": "boolean"
},
"converted": {
"type": [
"string",
"null"
]
},
"gtin14": {
"type": [
"string",
"null"
]
},
"indicator": {
"type": [
"string",
"null"
]
},
"normalised": {
"type": "string"
},
"reason": {
"type": [
"string",
"null"
]
},
"type": {
"type": "string"
},
"valid": {
"type": "boolean"
}
},
"type": "object"
},
"meta": {
"properties": {
"computed_at": {
"description": "RFC 3339 UTC with milliseconds",
"type": "string"
},
"deterministic": {
"type": "boolean"
},
"disclaimer": {
"type": "string"
},
"price_usd": {
"type": "string"
},
"request_id": {
"type": "string"
},
"sources": {
"items": {
"required": [
"id",
"version",
"published"
],
"type": "object"
},
"type": "array"
}
},
"required": [
"request_id",
"computed_at",
"price_usd",
"deterministic",
"disclaimer"
],
"type": "object"
},
"ok": {
"const": true
},
"route": {
"const": "/v1/id/gs1"
},
"version": {
"type": "string"
}
},
"required": [
"ok",
"route",
"version",
"data",
"meta"
],
"type": "object"
},
"type": {
"type": "string"
}
},
"required": [
"type"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
}