Aztec Code Generator

Compact 2D code with bullseye finder; standard on airline mobile boarding passes.

How Aztec Code is structured

Aztec Code centres the payload on a concentric square bullseye finder pattern, with a reference grid radiating outward so the reader can correct for perspective and print distortion. Data is organised in layers — compact symbols use up to 4 layers, full-range symbols up to 32 — and because the finder sits in the middle, the symbol needs no quiet zone beyond the smallest usable margin.

Aztec Code check digit

Error correction is Reed-Solomon, and the amount is chosen as a percentage of the symbol rather than as a fixed level: from about 5% up to 95%. The encoder default here is 23%. A higher percentage means fewer data codewords in the same symbol, so boarding passes typically run a high level for a short payload and a lower one for long text.

Aztec Code compared with PDF417

QR Code needs three quiet zones around its finder patterns and is the default for consumer scanning; Aztec fits a smaller footprint and tolerates rough printing, which is why tickets and transport passes use it. PDF417 carries more data but needs far more room, and Data Matrix beats both on density for very short payloads. Compare the PDF417 generator page for the same breakdown of structure, check digit and use cases.

Common Aztec Code problems

The error correction percentage is too high for the data

At 90% correction almost nothing is left for the message, so the payload silently stops fitting. Lower the percentage, or split the data, instead of assuming the symbol will simply grow.

A phone QR reader will not open it

Aztec is well supported but not universal, and many camera apps try QR first. Test with the reader class that will actually be used — a gate or turnstile scanner — rather than with a general-purpose phone app.

The bullseye is broken by the background

The concentric finder has to stay intact and high-contrast; a design that lets a border, a fold or a dark print colour run through the centre kills acquisition even with error correction. Keep the centre clear.

Where Aztec Code is used

Not sure this is the right symbology? The barcode format guide groups every supported 1D and 2D format by industry with its character set and limits.