Exploring the Color #51A688

#51A688 sits at 159° on the color wheel, placing it in the spring green family of the cool half of the spectrum. With 34% saturation and 48% 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 81, 166, 136 produces a 7.16:1 contrast ratio against black, which clears WCAG AAA for body text in that pairing.

In RGB space #51A688 is a clear variant of CSS steel blue — about 58 units away from #4682B4. Designers reach for spring green 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