# BarcodeFYI

> The Barcode Encyclopedia & Toolkit — 30 symbologies, guides, and tools.

## Markdown Endpoints

Every page supports `.md` suffix for LLM-friendly markdown:
- https://barcodefyi.com/symbology/ean-13.md
- https://barcodefyi.com/guide/barcode-fundamentals.md
- https://barcodefyi.com/glossary/quiet-zone.md

## Content Index

### Symbologies
- [UPC-A](https://barcodefyi.com/symbology/upc-a/.md): UPC-A barcode — the 12-digit product code that started retail scanning in 1974. Technical specs, check digit algorithm, and usage guide.
- [EAN-13](https://barcodefyi.com/symbology/ean-13/.md): EAN-13 barcode — the 13-digit global retail product code used in 100+ countries. Specs, GS1 prefix lookup, and check digit calculation.
- [ISBN (Bookland)](https://barcodefyi.com/symbology/isbn/.md): ISBN barcode — the international book identifier encoded as EAN-13 with 978/979 prefix. ISBN-10 to ISBN-13 conversion guide.
- [Code 39](https://barcodefyi.com/symbology/code-39/.md): Code 39 barcode — the first alphanumeric symbology, self-checking and widely used in defense, automotive, and healthcare since 1974.
- [Code 128](https://barcodefyi.com/symbology/code-128/.md): Code 128 barcode — the highest-density linear symbology with full ASCII support and three switchable character sets.
- [ITF-14](https://barcodefyi.com/symbology/itf-14/.md): ITF-14 barcode — the 14-digit standard for shipping cartons and cases with bearer bars for reliable corrugated cardboard scanning.
- [GS1-128](https://barcodefyi.com/symbology/gs1-128/.md): GS1-128 barcode — the supply chain standard encoding batch, expiry, and serial data with Application Identifiers.
- [Data Matrix](https://barcodefyi.com/symbology/data-matrix/.md): Data Matrix barcode — a 2D matrix code storing 2,335+ characters with error correction for direct part marking and industrial use.
- [PDF417](https://barcodefyi.com/symbology/pdf417/.md): PDF417 barcode — a stacked symbology encoding 1,850+ characters, standard for driver's licenses and boarding passes.
- [GS1 DataMatrix](https://barcodefyi.com/symbology/gs1-datamatrix/.md): GS1 DataMatrix — the 2D barcode for pharmaceutical serialization and medical device UDI with GS1 Application Identifiers.

### Reference
- [All Symbologies](https://barcodefyi.com/symbology.md)
- [GS1 Prefixes](https://barcodefyi.com/prefix.md)
- [Standards](https://barcodefyi.com/standard.md)
- [Check Digit Algorithms](https://barcodefyi.com/check-digit.md)
- [Glossary](https://barcodefyi.com/glossary.md)

### Guides & Tools
- [Guides](https://barcodefyi.com/guide.md)
- [Tools](https://barcodefyi.com/tools/)
- [Comparisons](https://barcodefyi.com/compare.md)

- Full reference: https://barcodefyi.com/llms-full.txt

## Related
- [QRCodeFYI](https://qrcodefyi.com/llms.txt) — The QR Code Encyclopedia & Toolkit
- [NFCFYI](https://nfcfyi.com/llms.txt) — The NFC Encyclopedia & Toolkit
- [BLEFYI](https://blefyi.com/llms.txt) — The BLE Encyclopedia & Toolkit
- [RFIDFYI](https://rfidfyi.com/llms.txt) — The RFID Encyclopedia & Toolkit
- [SmartCardFYI](https://smartcardfyi.com/llms.txt) — The Smart Card Encyclopedia & Toolkit