What Color Is Indigo?

The short answer

Indigo is a deep, saturated blue that leans toward violet. It sits between blue and violet in the traditional sequence of rainbow colors, and it is darker and more muted than a bright royal blue. Most people would describe it as a dark blue-purple, but the exact shade depends on which definition of indigo you are using.

For logo work, "indigo" is a family of shades, not a single color. Before it can be used reliably in artwork, it has to be pinned to specific values in each color space the logo will be delivered in.

Where the name comes from

The word comes from indigo dye, a deep blue colorant traditionally made from plants of the Indigofera genus and long associated with dyed textiles such as denim. Isaac Newton included indigo as one of the seven named colors when he divided the visible spectrum, which is why it appears in the familiar rainbow sequence between blue and violet. Many modern color references do not treat indigo as a separate spectral band, so its position as a distinct rainbow color is partly a matter of naming convention rather than a sharp physical boundary.

Why indigo looks different from source to source

Indigo can look noticeably bluer or noticeably more purple depending on the reference. The traditional dye tends toward a deep, slightly grayed blue. The named web color "indigo" defined in CSS is much more purple, with the hex value #4B0082 (RGB 75, 0, 130). Paint, textile and print color systems each publish their own indigo-named shades, and those do not necessarily match each other.

Because of this, saying a logo is "indigo" is not enough to reproduce it. Two designers working from the same word can produce visibly different results.

Defining indigo in a vector logo palette

A vector logo stores fill and stroke colors as numeric values, so an indigo palette entry should be recorded as exact values for each intended use rather than as a color name. A practical palette definition usually covers:

• A hex or RGB value for screens, websites and apps
• A CMYK value for standard process printing
• A spot color reference, if the brand prints with a specific ink system
• A note on which value is the master and which are matched conversions

In editable artwork, applying indigo as a named global swatch rather than as loose fill values makes it easier to adjust the shade across every path at once. That only works for genuine vector shapes. If part of the logo is an embedded raster image, or the file is just a raster preview saved in a vector-capable format, changing the swatch will not recolor it. A file extension alone does not confirm that the artwork is made of editable paths; the file needs to be opened and inspected.

Practical considerations when using indigo

• Print conversion: saturated violet-blues can fall outside what standard CMYK printing reproduces, so a converted indigo may print duller or bluer than it looks on screen. Proofing the CMYK value is advisable.
• Small sizes and dark backgrounds: a very deep indigo can read as near-black in small favicons or on dark surfaces. Testing the mark at its smallest intended size and checking contrast against its backgrounds helps.
• Reversed versions: a light or white version of the logo is often needed for use on indigo backgrounds, and that version should be part of the delivered file set.
• Screen variation: the same RGB value can appear slightly different across displays, so on-screen judgment should not replace documented values.

What this article cannot confirm

No specific brand guidelines, measured color samples or printed proofs were supplied for this overview, so it does not give a recommended CMYK or spot-color equivalent for indigo. Those values depend on the chosen master shade, the printing process and the paper or material, and should be confirmed with the relevant color system documentation or a print provider. If you are working from someone else's indigo logo, having a downloadable file does not by itself grant permission to modify the artwork or use the trademark.