ToolNestFree Online Barcode Generator
Quick answer: Create scannable barcodes in seconds. Our free barcode generator turns any text or number into a Code 39 barcode — the workhorse symbology for inventory, labels, and asset tracking — rendered as a crisp vector graphic you can download or print at any size. No signup, no watermark, and everything runs in your browser.
Create scannable barcodes in seconds. Our free barcode generator turns any text or number into a Code 39 barcode — the workhorse symbology for inventory, labels, and asset tracking — rendered as a crisp vector graphic you can download or print at any size. No signup, no watermark, and everything runs in your browser.
✓ Free forever · ✓ No signup · ✓ Runs in your browser — your data never leaves your device.
How to Use the Barcode Generator
- Type the text or numbers you want to encode — letters are auto-converted to uppercase.
- Tick 'Add Mod-43 check digit' if your inventory system requires a checksum character.
- Adjust the bar height and width, and pick a bar color if you need something other than black.
- Preview the barcode above — it renders instantly as you type.
- Download the vector SVG for print work or the high-res PNG for quick use.
Why Use Our Barcode Generator?
- True Code 39 encoding — the industry-standard 1D symbology, scannable by any barcode reader or phone app.
- Vector SVG downloads — infinitely scalable for packaging, labels, and professional print.
- Optional Mod-43 check digit — adds the checksum character many inventory systems require.
- Print-ready sizing — tune bar height and width so the code scans reliably on your printer.
- 100% private — encoding happens entirely in your browser; your product data is never uploaded.
Frequently Asked Questions
What kind of barcode does this generator make?
Code 39 (also called Code 3 of 9) — one of the oldest and most widely supported 1D barcode symbologies. It encodes uppercase letters, digits, and a handful of symbols, and virtually every scanner and phone barcode app reads it.
Will these barcodes actually scan?
Yes. The generator implements the official Code 39 spec: start/stop characters, inter-character gaps, and a 10-module quiet zone on each side. For reliable scans, print at least ~2.5 cm (1 inch) wide with high contrast (dark bars on a light background) and test-scan one before printing in bulk.
What characters can I encode?
A–Z, 0–9, space, and the symbols - . $ / + %. Lowercase letters are converted to uppercase automatically, since Code 39 is uppercase-only. Any unsupported character is stripped and flagged with a warning.
Why did my lowercase text become uppercase?
Code 39 has no lowercase characters in its alphabet — 43 symbols total. The generator converts lowercase to uppercase rather than silently dropping it, so nothing you typed disappears.
What is the Mod-43 check digit?
An optional error-detection character appended to the data: the values of all characters are summed and divided by 43, and the remainder maps to one more Code 39 character. Some inventory and logistics systems require it; most casual uses don't.
Is it free for commercial use?
Yes. Barcodes you generate are yours — use them on products, packaging, shipping labels, and asset tags with no fees, watermarks, or attribution required.