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I printed my QR code in my gold brand color on white and now it will not scan. Why?

Because the contrast is weak. Cameras need dark modules on a light background with a clear difference, and gold #d4af37 on white gives a contrast ratio of just 2.10 to 1, which the tool classes as 'low'. The fix is a darker shade of your brand color, or a black code with a gold frame around it.

Published · 3 min read

What the tool says about your colors

When you change the 'Module color' and 'Background color' in the QR code generator, the tool calculates the contrast ratio and warns you. Its rule: below 2 to 1 the code is probably unscannable, between 2 and 4 it is unreliable, and 4 to 1 or more is good. That rule is the tool's own, based on the WCAG measure rather than the QR specification, and the real outcome depends on printer, lighting and camera. We tried several colors on white:

  • Light gold #d4af37: ratio 2.10, with the 'contrast is low' warning.
  • Dark gold #8a6d1f: ratio 4.89, no warning.
  • Deeper golden brown #6b5414: ratio 7.23.
  • Dark green #0f6b5f: ratio 6.38.
  • Grey #777777 on a grey #999999 background: ratio 1.57, and the tool says the code is probably unscannable.

Why it worked on screen and failed on paper

A screen lights colors from behind, so gold looks clearer than it is. On paper the ink absorbs light, and gold can come out duller depending on the printer and paper, and then warm shop lighting pulls the two colors even closer. A code at 2.10 on screen can be worse in practice once printed. So always print a test copy before the full run.

Fixes that keep your brand look

  1. Pick a darker shade of the same color until the warning disappears. You can try shades quickly in the Color contrast checker and then carry the best one into the tool.
  2. Make the code black on white and put the gold in a frame around it or in the text beside it, keeping the quiet zone white.
  3. Do not invert the colors. Gold on a black background gives a ratio of 9.98, but the tool still warns because the modules are lighter than the background, and many readers refuse an inverted code even at high contrast.
  4. Once the colors are chosen, print on the real paper and scan it under your shop's lighting.

Common questions

Is a gradient inside the code acceptable?

The tool does not make gradients; it uses two solid colors only. If you add a gradient in design software, its lightest part is what sets the real contrast.

Can I place the code over a product photo?

The tool draws a solid background in the color you choose and calculates contrast on that basis. If you remove that background in design software and set the code over a photo, the contrast is completely different from what the tool calculated, so keep the solid background.