#255171
Closest named color: Deep Sea Blue (#015482). oklch(41.9% 0.072 242.7), rgb(37, 81, 113).
Aa
White text reads best on this color (8.41:1).
About this color
#255171 is a dark, moderately saturated blue. In OKLCH its lightness is 42%, its chroma 0.072 and its hue 243°. Its hue sits on the cool side of the wheel. The nearest named color is Deep Sea Blue (#015482), ΔE 0.031 away. White text reads best on it, at 8.41:1.
| Hue family | Blues |
| Lightness | dark (42%) |
| Chroma | moderately saturated (0.072) |
| Temperature | cool |
| Nearest name | Deep Sea Blue (#015482) |
| Black text | 2.49:1 |
| White text | 8.41:1 |
Values
| HEX | #255171 |
| RGB | rgb(37, 81, 113) |
| HSL | hsl(205, 51%, 29%) |
| OKLCH | oklch(41.9% 0.072 242.7) |
Contrast
WCAG 2 contrast ratios are the conformance target: AA needs 4.5:1 for body text and 3:1 for large text, AAA needs 7:1. APCA Lc values are supplementary guidance from the WCAG 3 drafts.
| Pair | WCAG 2 | Result | APCA | APCA guidance |
|---|---|---|---|---|
| White text on #255171 | 8.41:1 | AAA | Lc -93.4 | Preferred for body text |
| Black text on #255171 | 2.49:1 | Fails | Lc 15.2 | Dividers and decoration only |
| #255171 text on white | 8.41:1 | AAA | Lc 88.8 | Fine for body text |
| #255171 text on black | 2.49:1 | Fails | Lc -13.4 | Not readable |
Tints and shades
A 50–950 scale built in OKLCH: the hue is held, lightness follows a Tailwind v4-like curve, and every step is kept inside the sRGB gamut. This color sits at step 800.
-
Step 50
50
#F2F6F9
oklch(97.1% 0.006 239.8)
-
Step 100
100
#E3EBF2
oklch(93.6% 0.013 244.3)
-
Step 200
200
#CCDBE8
oklch(88.4% 0.024 244.2)
-
Step 300
300
#AAC4DA
oklch(80.8% 0.042 243.8)
-
Step 400
400
#7CA6C8
oklch(70.7% 0.068 243.3)
-
Step 500
500
#5990BA
oklch(63.2% 0.086 242.7)
-
Step 600
600
#3C79A6
oklch(55.5% 0.095 243)
-
Step 700
700
#2E668E
oklch(49.1% 0.087 242.5)
-
Step 800
800 (this color)
#255171
oklch(41.9% 0.072 242.7)
-
Step 900
900
#25455D
oklch(37.7% 0.056 242.6)
-
Step 950
950
#162837
oklch(26.9% 0.037 244.9)
#255171 with color blindness
Simulated with the Machado et al. (2009) model. ΔE is how far the color moves: below about 0.02 you would not notice a change.
| Vision | Seen as | Shift (ΔE) |
|---|---|---|
| Protanopia (no red cones) | #435172 | 0.035 |
| Deuteranopia (no green cones) | #384A70 | 0.028 |
| Tritanopia (no blue cones) | #00595C | 0.054 |
| Achromatopsia (no color) | #4D4D4D | 0.072 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #255171
#255171
oklch(41.9% 0.072 242.7)
- #69431F
#69431F
oklch(41.9% 0.073 62)
Analogous
Neighbouring hues, 30° either side.
Split complementary
The two hues beside the complement (150° and 210°).
Triadic
Three hues spaced 120° apart.
Palettes with this color
Curated palettes that contain a color within ΔE 0.04 (OKLab) of #255171, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Deep Sea Blue #015482 ΔE 0.031
- Light Navy #155084 ΔE 0.034
- Dark Grey Blue #29465B ΔE 0.044
- Light Navy Blue #2E5A88 ΔE 0.045
- YInMn Blue #415A77 ΔE 0.045
- Dusk Blue #26538D ΔE 0.047
- Petrol #005F6A ΔE 0.051
- Deep Teal #00555A ΔE 0.051
Use #255171 in your product
Turn it into light and dark UI roles checked for contrast, then export to Tailwind v4, shadcn/ui, CSS or design tokens.