QR code contrast that scanners can read

Most phone scanners are tuned for dark data modules against a lighter field. Light-on-dark (inverted) codes sometimes work and sometimes fail unpredictably across devices and apps.

Keep finder patterns high-contrast and recognizable. If you recolor finders separately from modules, make sure they remain clearly darker than the local background.

Gradients look polished in Design Studio previews, but they can locally flatten contrast—especially near finder corners or across sparse module regions. Soft fades toward the background color are a frequent scan complaint.

If you use a gradient fill, keep the lightest module regions still clearly darker than the background, and re-test after any export or print conversion. Protect finder clarity even when modules are stylized.

QRburst’s Lab contrast signals borrow WCAG-style relative luminance math familiar from accessibility work. That gives creators a consistent, explainable warning when foreground and background are too close.

Explicit product note: WCAG contrast is a QRburst heuristic for Lab guidance. It is not a QR symbology standard and is not how phone decoders formally score a symbol. Passing a Lab contrast check improves the odds of a readable design; it is not proof of decode success.

Screens are backlit; print is reflective. Colors that look crisp on a calibrated display can muddy on uncoated stock, colored paper, or under warm restaurant lighting.

Proof on the real substrate. If contrast drops after printing, darken modules, lighten the background patch behind the code, or switch to a more neutral paper. Glare from gloss finishes can erase contrast even when the ink values are fine—matte often scans more reliably.