#255999
Closest named color: Dusk Blue (#26538D). oklch(46.3% 0.118 255.3), rgb(37, 89, 153).
Aa
White text reads best on this color (7.07:1).
About this color
#255999 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 46%, its chroma 0.118 and its hue 255°. Its hue sits on the cool side of the wheel. The nearest named color is Dusk Blue (#26538D), ΔE 0.024 away. White text reads best on it, at 7.07:1.
| Hue family | Blues |
| Lightness | medium-dark (46%) |
| Chroma | moderately saturated (0.118) |
| Temperature | cool |
| Nearest name | Dusk Blue (#26538D) |
| Black text | 2.96:1 |
| White text | 7.07:1 |
Values
| HEX | #255999 |
| RGB | rgb(37, 89, 153) |
| HSL | hsl(213, 61%, 37%) |
| OKLCH | oklch(46.3% 0.118 255.3) |
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 #255999 | 7.07:1 | AAA | Lc -89.1 | Fine for body text |
| Black text on #255999 | 2.96:1 | Fails | Lc 19.8 | Dividers and decoration only |
| #255999 text on white | 7.07:1 | AAA | Lc 84.2 | Fine for body text |
| #255999 text on black | 2.96:1 | Fails | Lc -17.8 | Dividers and decoration only |
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 700.
-
Step 50
50
#F2F6FB
oklch(97.2% 0.008 253.9)
-
Step 100
100
#E3EBF5
oklch(93.7% 0.016 253.9)
-
Step 200
200
#CCDBEE
oklch(88.6% 0.031 254.3)
-
Step 300
300
#A8C3E6
oklch(80.9% 0.058 255)
-
Step 400
400
#7AA3D9
oklch(70.7% 0.091 255.6)
-
Step 500
500
#578BCF
oklch(63% 0.117 255.7)
-
Step 600
600
#3B74BC
oklch(55.6% 0.128 255.4)
-
Step 700
700 (this color)
#255999
oklch(46.3% 0.118 255.3)
-
Step 800
800
#275083
oklch(42.8% 0.097 255.1)
-
Step 900
900
#244269
oklch(37.6% 0.076 255.7)
-
Step 950
950
#16273E
oklch(27% 0.049 256.3)
#255999 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) | #3A5E9C | 0.027 |
| Deuteranopia (no green cones) | #275398 | 0.017 |
| Tritanopia (no blue cones) | #006871 | 0.091 |
| Achromatopsia (no color) | #585858 | 0.118 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #255999
#255999
oklch(46.3% 0.118 255.3)
- #785000
#785000
oklch(46.4% 0.098 75.7)
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 #255999, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dusk Blue #26538D ΔE 0.024
- Denim Blue #3B5B92 ΔE 0.025
- Light Navy Blue #2E5A88 ΔE 0.029
- Dusky Blue #475F94 ΔE 0.043
- Peacock Blue #016795 ΔE 0.043
- Light Navy #155084 ΔE 0.044
- Deep Sea Blue #015482 ΔE 0.046
- Denim #3B638C ΔE 0.046
Use #255999 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.