Nail the exact color indigo in your design by using the code from any one of these systems for color identification.
|RGB||r: 75, g: 0, b: 130|
|HSL||h: 275°, s: 100%, l: 25%|
|HSV||h: 275°, s: 100%, v: 51%|
|CMYK||c: 42%, m: 100%, y: 0%, k: 49%|
If you're identifying color for pretty much anything digital, you're working in an RGB colorspace. If the project you're working on requires percentage representation, indigo is made of 29% red, 0% green, and 51% blue.
If you're identifying color for a print project, you're most likely using a CMYK colorspace—the percentages are 42% cyan, 100% magenta, 0% yellow, 49% black.