How QR codes work

A QR code combines reserved functional modules with placed codeword bits. Some versions also need a few remainder bits to complete the placement path. Configure a symbol, then hover or focus any module to see which region it belongs to. Click, tap, or press Enter to pin a selection.

Configure

Reset

Payloadhttps://qrcodesdk.dev

UTF-8 ECI

Emit assignment 26 before the first octet segment to explicitly declare UTF-8.

ModeAuto

VersionAuto

Error CorrectionAuto

MaskAuto

Size

Quiet zone

V2 octet ECC M Mask 2 25×25 modules

QR anatomy

Hover to preview · click to pin

Quiet zone 464 Functional modules 266 Encoded modules 352 Remainder bits 7

Inspect a module

Hover any square to reveal its job. Click, tap, or press Enter to keep a selection pinned while you explore.