#233B87
Closest named color: Cobalt (#1E488F). oklch(38.1% 0.131 266.8), rgb(35, 59, 135).
Aa
White text reads best on this color (10.25:1).
About this color
#233B87 is a dark, moderately saturated blue. In OKLCH its lightness is 38%, its chroma 0.131 and its hue 267°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.036 away. White text reads best on it, at 10.25:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | moderately saturated (0.131) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.04:1 |
| White text | 10.25:1 |
Values
| HEX | #233B87 |
| RGB | rgb(35, 59, 135) |
| HSL | hsl(226, 59%, 33%) |
| OKLCH | oklch(38.1% 0.131 266.8) |
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 #233B87 | 10.25:1 | AAA | Lc -97.5 | Preferred for body text |
| Black text on #233B87 | 2.04:1 | Fails | Lc 10.5 | Not readable |
| #233B87 text on white | 10.25:1 | AAA | Lc 93.4 | Preferred for body text |
| #233B87 text on black | 2.04:1 | Fails | Lc -9.1 | 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
#F1F5FF
oklch(97% 0.014 268.5)
-
Step 100
100
#E1EAFE
oklch(93.6% 0.029 266.4)
-
Step 200
200
#C9D9FE
oklch(88.5% 0.054 266.8)
-
Step 300
300
#A5BFFF
oklch(80.9% 0.095 267.2)
-
Step 400
400
#759BFF
oklch(70.6% 0.153 266.8)
-
Step 500
500
#537EFF
oklch(63.1% 0.197 266.8)
-
Step 600
600
#3A62F0
oklch(55.5% 0.218 266.9)
-
Step 700
700
#2D50D1
oklch(49.1% 0.202 266.7)
-
Step 800
800
#2643A9
oklch(42.8% 0.167 266.8)
-
Step 900
900 (this color)
#233B87
oklch(38.1% 0.131 266.8)
-
Step 950
950
#14234E
oklch(27.1% 0.082 266.5)
#233B87 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) | #00458A | 0.031 |
| Deuteranopia (no green cones) | #003C85 | 0.024 |
| Tritanopia (no blue cones) | #004D5B | 0.103 |
| Achromatopsia (no color) | #414141 | 0.131 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #233B87
#233B87
oklch(38.1% 0.131 266.8)
- #553F00
#553F00
oklch(38.1% 0.078 86.2)
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 #233B87, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.036
- Twilight Blue #0A437A ΔE 0.037
- Dark Slate Blue #483D8B ΔE 0.054
- Marine Blue #01386A ΔE 0.058
- Blueberry #464196 ΔE 0.059
- Sapphire #2138AB ΔE 0.060
- Light Navy #155084 ΔE 0.060
- Dusk Blue #26538D ΔE 0.068
Use #233B87 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.