When you see a QR code, it’s not too difficult to imagine the code in a grid, like dark tiles on a Scrabble board, or a pattern laid out on graph paper. When a mobile camera snaps a picture of a QR code, it lays the image out on a grid, it uses an algorithm to “square up” the code if it’s skewed, then it evaluates “the grid” to see which of them contain dark tiles and which contain light tiles.
A QR code scan program decodes a QR code by analyzing the contrast of a QR code. The contrast may be moderate, it doesn’t have to be absolute black and white. Put another way, the QR code reader program can decode a QR code constructed of a variety of colors as long as it can clearly see a contrast between what is to be the background and the pixels and QR code elements. A detectable contrast and a common solid background color is important when making a colored QR code.
When creating a color QR code, keep in mind that QR code readers are most reliable when the QR code contrast is great. That is, the dark elements of the QR code should be somewhat dark and the QR code’s consistent background should be somewhat light. If your colored QR code does not have a lot of contrast, some QR code scanner apps may be unable to read it and your colored QR code may be more unreadable in low light than a typical black and white QR code.
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So, keeping QR code contrast in mind, you can use any of the websites in the list below to create color QR codes. Or you can create a standard black and white QR code, save it in a .PNG or .JPG format, then use any image editing program such as Photoshop or JASC to manually change the colors of the pixels or elements of the QR code.
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