API-referens

Generate Code 128 and GS1 barcodes programmatically. Simple REST API with JSON responses and image downloads.

Free: 100 req/day Business: 50,000 req/month

Snabbstart

curl "https://www.barcode-code128.com/api/barcode/render?value=HELLO-WORLD&format=PNG&resolution=300" --output barcode.png

Endpoints

GET /api/barcode/render Download a barcode image

Parameter	Type	Default	Description
value	string	—	Required. The barcode content to encode.
symbology	string	Code128Auto	Code128Auto, Code128A, Code128B, Code128C, GS1_128, GS1_DataMatrix, GS1_QR
format	string	PNG	PNG, SVG, PDF, EPS
resolution	int	300	DPI: 150, 300, 600, 1200
xDimension	decimal	0.33	Bar module width in mm
barHeight	decimal	25.4	Bar height in mm
showText	bool	true	Show human-readable text below barcode
foregroundColor	string	#000000	Bar color (hex)
backgroundColor	string	#FFFFFF	Background color (hex)
barWidthReduction	decimal	0	Print correction in mm

POST /api/barcode/batch Generate multiple barcodes as ZIP

Send a JSON body with an array of values. Returns a ZIP file containing one barcode per value.

{
  "values": ["SKU-001", "SKU-002", "SKU-003"],
  "symbology": "Code128Auto",
  "format": "PNG",
  "resolution": 300
}

POST /api/gs1/render Generate a GS1 barcode from structured data

Send GS1 Application Identifier fields. The API handles encoding, FNC1 separators, and check digits.

{
  "fields": [
    { "ai": "01", "value": "05412345000013" },
    { "ai": "10", "value": "LOT-A23" },
    { "ai": "17", "value": "260731" }
  ],
  "symbology": "GS1_128",
  "format": "PNG",
  "resolution": 300
}

GET /api/barcode/quota Check your current usage

{ "usedToday": 3, "dailyLimit": 5, "remaining": 2, "tier": "Free" }

Playground

Try the API live — no signup required.

Value

Format

DPI

cURL

Kodexempel

cURL

curl "https://www.barcode-code128.com\
/api/barcode/render\
?value=SKU-4711\
&format=PNG\
&resolution=300" \
  --output barcode.png

Python

import requests

resp = requests.get(
    "https://www.barcode-code128.com"
    "/api/barcode/render",
    params={
        "value": "SKU-4711",
        "format": "PNG",
        "resolution": 300
    }
)

with open("barcode.png", "wb") as f:
    f.write(resp.content)

Node.js

const fs = require('fs');

const url = new URL(
  "https://www.barcode-code128.com"
  + "/api/barcode/render"
);
url.searchParams.set("value", "SKU-4711");
url.searchParams.set("format", "PNG");
url.searchParams.set("resolution", "300");

const resp = await fetch(url);
const buf = await resp.arrayBuffer();
fs.writeFileSync(
  "barcode.png",
  Buffer.from(buf)
);