Exploring the Color #5B5FB1

#5B5FB1 sits at 237° on the color wheel, placing it in the blue family of the cool half of the spectrum. With 36% saturation and 53% lightness, it reads as a softly muted, balanced tone — a balanced mid-energy presence that sits comfortably alongside other UI tones. Its RGB mix of 91, 95, 177 produces a 5.65:1 contrast ratio against white, which clears WCAG AA for body text in that pairing.

In RGB space #5B5FB1 is a clear variant of CSS slate blue — about 32 units away from #6A5ACD. Designers reach for blue hues at this saturation when the brief calls for a conversational, mid-energy register, and at this lightness when they want a present, comfortable mid-canvas voice. On screen the cool cast tends to pair best with warm neutrals in the 25°-45° range to add life.

Darkening Shades

Lightening Shades