#10599B
Closest named color: Dusk Blue (#26538D). oklch(45.9% 0.126 251.5), rgb(16, 89, 155).
Aa
White text reads best on this color (7.18:1).
About this color
#10599B is a medium-dark, moderately saturated blue. In OKLCH its lightness is 46%, its chroma 0.126 and its hue 252°. Its hue sits on the cool side of the wheel. The nearest named color is Dusk Blue (#26538D), ΔE 0.027 away. White text reads best on it, at 7.18:1.
| Hue family | Blues |
| Lightness | medium-dark (46%) |
| Chroma | moderately saturated (0.126) |
| Temperature | cool |
| Nearest name | Dusk Blue (#26538D) |
| Black text | 2.92:1 |
| White text | 7.18:1 |
Values
| HEX | #10599B |
| RGB | rgb(16, 89, 155) |
| HSL | hsl(208, 81%, 34%) |
| OKLCH | oklch(45.9% 0.126 251.5) |
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 #10599B | 7.18:1 | AAA | Lc -89.3 | Fine for body text |
| Black text on #10599B | 2.92:1 | Fails | Lc 19.6 | Dividers and decoration only |
| #10599B text on white | 7.18:1 | AAA | Lc 84.4 | Fine for body text |
| #10599B text on black | 2.92:1 | Fails | Lc -17.6 | 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 800.
-
Step 50
50
#F1F6FC
oklch(97.1% 0.01 252.8)
-
Step 100
100
#E0EBF8
oklch(93.6% 0.021 252.5)
-
Step 200
200
#C6DCF4
oklch(88.6% 0.041 250.6)
-
Step 300
300
#9EC4EF
oklch(80.8% 0.074 251.8)
-
Step 400
400
#67A5E8
oklch(70.8% 0.118 251.5)
-
Step 500
500
#388CE1
oklch(63% 0.151 251.8)
-
Step 600
600
#0074CF
oklch(55.5% 0.165 251.7)
-
Step 700
700
#0062AF
oklch(49.2% 0.144 251.3)
-
Step 800
800 (this color)
#10599B
oklch(45.9% 0.126 251.5)
-
Step 900
900
#104374
oklch(37.8% 0.099 251.7)
-
Step 950
950
#0C2744
oklch(26.9% 0.063 252.6)
#10599B 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) | #375E9E | 0.035 |
| Deuteranopia (no green cones) | #1E529A | 0.020 |
| Tritanopia (no blue cones) | #006972 | 0.093 |
| Achromatopsia (no color) | #575757 | 0.126 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #10599B
#10599B
oklch(45.9% 0.126 251.5)
- #794D00
#794D00
oklch(45.9% 0.098 71.9)
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 #10599B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dusk Blue #26538D ΔE 0.027
- Light Navy Blue #2E5A88 ΔE 0.036
- Denim Blue #3B5B92 ΔE 0.037
- Light Navy #155084 ΔE 0.042
- Deep Sea Blue #015482 ΔE 0.043
- Peacock Blue #016795 ΔE 0.044
- Cobalt #1E488F ΔE 0.049
- Dusky Blue #475F94 ΔE 0.054
Use #10599B 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.