#2B3687
Closest named color: Cobalt (#1E488F). oklch(37.5% 0.135 272.3), rgb(43, 54, 135).
Aa
White text reads best on this color (10.60:1).
About this color
#2B3687 is a dark, moderately saturated blue. In OKLCH its lightness is 38%, its chroma 0.135 and its hue 272°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.048 away. White text reads best on it, at 10.60:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | moderately saturated (0.135) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 1.98:1 |
| White text | 10.60:1 |
Values
| HEX | #2B3687 |
| RGB | rgb(43, 54, 135) |
| HSL | hsl(233, 52%, 35%) |
| OKLCH | oklch(37.5% 0.135 272.3) |
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 #2B3687 | 10.60:1 | AAA | Lc -98.2 | Preferred for body text |
| Black text on #2B3687 | 1.98:1 | Fails | Lc 9.7 | Not readable |
| #2B3687 text on white | 10.60:1 | AAA | Lc 94.2 | Preferred for body text |
| #2B3687 text on black | 1.98:1 | Fails | Lc -8.4 | 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 900.
-
Step 50
50
#F2F5FF
oklch(97.1% 0.014 272.7)
-
Step 100
100
#E3E9FE
oklch(93.6% 0.029 273.1)
-
Step 200
200
#CCD8FF
oklch(88.6% 0.055 271.8)
-
Step 300
300
#ABBDFF
oklch(80.9% 0.096 272.3)
-
Step 400
400
#8198FF
oklch(70.7% 0.153 272.5)
-
Step 500
500
#637AFF
oklch(63.2% 0.198 272.1)
-
Step 600
600
#4C5CF4
oklch(55.7% 0.225 272.1)
-
Step 700
700
#3E4AD4
oklch(49.1% 0.209 272.1)
-
Step 800
800
#333EAB
oklch(42.7% 0.172 272.3)
-
Step 900
900 (this color)
#2B3687
oklch(37.5% 0.135 272.3)
-
Step 950
950
#19214F
oklch(27% 0.085 272.1)
#2B3687 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) | #00438A | 0.042 |
| Deuteranopia (no green cones) | #003B85 | 0.035 |
| Tritanopia (no blue cones) | #004A59 | 0.111 |
| Achromatopsia (no color) | #3F3F3F | 0.135 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #2B3687
#2B3687
oklch(37.5% 0.135 272.3)
- #503F00
#503F00
oklch(37.5% 0.077 91.5)
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 #2B3687, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.048
- Twilight Blue #0A437A ΔE 0.049
- Dark Slate Blue #483D8B ΔE 0.051
- Blueberry #464196 ΔE 0.058
- Sapphire #2138AB ΔE 0.060
- Marine Blue #01386A ΔE 0.063
- Light Navy #155084 ΔE 0.073
- Dusk Blue #26538D ΔE 0.079
Use #2B3687 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.