Barcode API

The ChartQuery Barcode API generates barcode images in 25+ formats — EAN-13, EAN-8, UPC-A, Code 128, ITF-14, GS1-128, postal codes and more — as SVG (default) or PNG.

• Barcode API — Generate a barcode image via GET.

Use it for retail packaging, shipping, inventory, invoices and labels.

Endpoint	Request	Credits
Barcode API	GET /v1/barcode	3

Table of contents

• How it works
• Barcode API
• Code examples in other languages
• Use cases
• Why ChartQuery?
• FAQ
• Related repositories
• Support

How it works

1. Create a ChartQuery account and copy your API key from the dashboard.
2. Call https://api.chartquery.com with the header x-api-key: YOUR_API_KEY.
3. Use the result in your app — no infrastructure to run.

export CHARTQUERY_API_KEY="your-api-key"
pip install requests        # Python
# TypeScript: Node.js 18+ (native fetch), run with `npx tsx file.ts`

Barcode API

Generate a barcode image via GET. Output: SVG (default) or PNG. Supports 25+ formats: EAN-13, Code 128, ITF-14, GS1-128, postal codes and more.

GET https://api.chartquery.com/v1/barcode · 3 credits per request · API reference

Request parameters

Parameter	In	Type	Required	Description
data	query	string	✅	The data to encode in the barcode. Examples by type:
type	query	string (code128, code39, code39ext, code93, code93ext, ean13)	—	Barcode format. Default: code128.
height	query	number	—	Bar height in pixels. Default: 80. Typical values: 50 (compact), 80 (standard), 100–120 (tall labels). Example: ?height=100
color	query	string	—	Bar color as a CSS color string. Default: #000. Examples: ?color=%231e293b (dark slate), ?color=%230f172a (near black), ?color=%237c3aed (purple), ?color=%23dc2626 (red). Use %23 to URL-encode the # character.
show_text	query	boolean	—	Show human-readable text below the bars. Example: ?show_text=true. Combine with font_size and text_align for print labels.
text_position	query	string (bottom, top)	—	Position of the human-readable text label. Default: bottom. Example: ?text_position=top
text_align	query	string (center, left, right)	—	Horizontal alignment of the text label. Default: center. Example: ?text_align=left
font_size	query	number	—	Font size of the text label in pixels. Default: 14. Example: ?font_size=12
font_family	query	string	—	Font family of the text label. Default: monospace. Examples: ?font_family=monospace, ?font_family=sans-serif, ?font_family=Arial
bar_width	query	number	—	Width multiplier per module (bar). Default: 2. Increase for wider, more scannable barcodes. Example: ?bar_width=3
bar_gap	query	number	—	Extra horizontal spacing between bars in pixels. Default: 0. Example: ?bar_gap=1
background	query	string	—	Background fill color. Default: #fff. Use transparent for no background. Example: ?background=%23f8fafc
margin	query	number	—	Uniform margin around the barcode in pixels. Default: 10. Overridden per side by margin_top/bottom/left/right. Example: ?margin=6
margin_top	query	number	—	Top margin in pixels (overrides margin). Example: ?margin_top=4
margin_bottom	query	number	—	Bottom margin in pixels (overrides margin). Example: ?margin_bottom=4
margin_left	query	number	—	Left margin in pixels (overrides margin). Example: ?margin_left=8
margin_right	query	number	—	Right margin in pixels (overrides margin). Example: ?margin_right=8
rotation	query	number (0, 90, 180, 270)	—	Rotate the barcode by 0, 90, 180 or 270 degrees. Default: 0. Use 90 or 270 for vertical label orientation. Example: ?rotation=90
bearer_bars	query	boolean	—	Add horizontal bearer bars above and below the barcode. Required for ITF-14. Default: false. Example: ?bearer_bars=true
unit	query	string (px, mm, in, cm)	—	Measurement unit for dimensions. Default: px. Use mm, in or cm for print-ready output. Example: ?unit=mm
aria_label	query	string	—	Accessible label added as aria-label on the SVG element. Improves screen reader support. Example: ?aria_label=EAN-13+barcode+for+product+4006381333931
title	query	string	—	SVG <title> element for tooltip and accessibility. Example: ?title=Product+Barcode
desc	query	string	—	SVG element for extended accessibility description. Example: ?desc=EAN-13+encoding+GTIN+for+Nivea+cream+75ml
format	query	string (svg, png)	—	Output format. Default: svg. Use png to get a raster image. SVG is lossless and scalable; PNG is pixel-based and suitable for email, PDF or messaging. Example: ?format=png
share	query	boolean (false, true)	—	Set share=true to persist the config and receive JSON instead of an image: { id, render_url, view_url, embed_url, expires_in }. Free plan: 3-day expiry with watermark. Paid plan: 6-month expiry, no branding.

Python example

import os

import requests

API_KEY = os.environ["CHARTQUERY_API_KEY"]
HEADERS = {"x-api-key": API_KEY}

response = requests.get(
    "https://api.chartquery.com/v1/barcode",
    headers=HEADERS,
    params={
        "data": "HELLO-WORLD-2026",
    },
    timeout=120,
)
response.raise_for_status()

with open("barcode.svg", "wb") as f:
    f.write(response.content)
print("Saved barcode.svg", len(response.content), "bytes")

TypeScript example

import { writeFile } from "node:fs/promises";

const headers = { "x-api-key": process.env.CHARTQUERY_API_KEY!, "Content-Type": "application/json" };

const params = new URLSearchParams({
  "data": "HELLO-WORLD-2026",
});

const response = await fetch(`https://api.chartquery.com/v1/barcode?${params}`, { headers });
if (!response.ok) throw new Error(`HTTP ${response.status}: ${await response.text()}`);

await writeFile("barcode.svg", Buffer.from(await response.arrayBuffer()));
console.log("Saved barcode.svg");

Output

The response body is the generated file (saved as barcode.svg in every example). Error responses are JSON with an explanatory message.

Code examples in other languages

Ready-to-run examples live in examples/; each reads your key from CHARTQUERY_API_KEY.

Language	barcode
cURL (Bash)	barcode.sh
PHP	barcode.php
C#	Barcode.cs
Go	barcode.go
Java	BarcodeExample.java
Ruby	barcode.rb
Node.js	barcode.mjs

Use cases

• Retail & packaging — EAN/UPC barcodes for products.
• Logistics — Code 128 / GS1-128 for shipping and inventory.
• Documents — Barcodes on invoices and delivery notes.

Why ChartQuery?

• Images in one request — the response body is the PNG/SVG/PDF, ready for emails, PDFs, dashboards, Slack or <img> tags.
• Charts, diagrams, QR codes, barcodes, labels — Chart.js configs, 28 diagram languages (Mermaid, Graphviz, PlantUML, D2…), 25+ barcode formats.
• AI generation — describe a chart or diagram in plain English and get the rendered image.
• No rendering infrastructure — no headless browser, fonts or libraries to maintain.
• Copy-paste examples — Python and TypeScript in each README, 7 more languages in examples/.

FAQ

How do I authenticate?

Create an account on ChartQuery, copy your API key and send it in the x-api-key header of every request to https://api.chartquery.com.

How much does a request cost?

Credits per call: /v1/barcode 3. See ChartQuery pricing.

What does the API return?

The response body is the file itself (image or document). Save it directly to disk or stream it to your storage — every example in this repository writes the file locally.

Which languages are supported?

Any language that can make an HTTP request. This README shows Python and TypeScript; the examples/ folder contains cURL, PHP, C#, Go, Java, Ruby and Node.js.

Related repositories

• Chart API
• Diagram API
• QR Code API
• Thermal Label API
• All ChartQuery repositories

Support

• 💬 Join the Discord to ask questions and share what you build.
• 📚 Read the API reference.
• 🔑 Get your API key.

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_{Built by ChartQuery. Examples are released under the MIT license.}