#233B9E
Closest named color: Sapphire (#2138AB). oklch(40.1% 0.163 267.7), rgb(35, 59, 158).
Aa
White text reads best on this color (9.58:1).
About this color
#233B9E is a dark, vivid blue. In OKLCH its lightness is 40%, its chroma 0.163 and its hue 268°. Its hue sits on the cool side of the wheel. The nearest named color is Sapphire (#2138AB), ΔE 0.022 away. White text reads best on it, at 9.58:1.
| Hue family | Blues |
| Lightness | dark (40%) |
| Chroma | vivid (0.163) |
| Temperature | cool |
| Nearest name | Sapphire (#2138AB) |
| Black text | 2.19:1 |
| White text | 9.58:1 |
Values
| HEX | #233B9E |
| RGB | rgb(35, 59, 158) |
| HSL | hsl(228, 64%, 38%) |
| OKLCH | oklch(40.1% 0.163 267.7) |
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 #233B9E | 9.58:1 | AAA | Lc -95.9 | Preferred for body text |
| Black text on #233B9E | 2.19:1 | Fails | Lc 12.4 | Not readable |
| #233B9E text on white | 9.58:1 | AAA | Lc 91.6 | Preferred for body text |
| #233B9E text on black | 2.19:1 | Fails | Lc -10.8 | 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
#E1EAFF
oklch(93.7% 0.03 267.2)
-
Step 200
200
#C9D9FF
oklch(88.6% 0.055 267.2)
-
Step 300
300
#A6BFFF
oklch(80.9% 0.095 267.8)
-
Step 400
400
#779BFF
oklch(70.7% 0.152 267.5)
-
Step 500
500
#567DFF
oklch(63% 0.198 267.8)
-
Step 600
600
#385BFF
oklch(55.5% 0.245 267.7)
-
Step 700
700
#2941EC
oklch(49% 0.252 267.7)
-
Step 800
800
#2138BF
oklch(42.7% 0.21 267.6)
-
Step 900
900 (this color)
#233B9E
oklch(40.1% 0.163 267.7)
-
Step 950
950
#112058
oklch(27.1% 0.103 267.5)
#233B9E 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) | #004BA1 | 0.041 |
| Deuteranopia (no green cones) | #003F9C | 0.022 |
| Tritanopia (no blue cones) | #005566 | 0.130 |
| Achromatopsia (no color) | #454545 | 0.163 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #233B9E
#233B9E
oklch(40.1% 0.163 267.7)
- #5B4500
#5B4500
oklch(40.3% 0.082 87.8)
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 #233B9E, closest first.
No curated palette has a color within ΔE 0.04 of #233B9E.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Sapphire #2138AB ΔE 0.022
- Cobalt #1E488F ΔE 0.043
- Blueberry #464196 ΔE 0.053
- Dark Slate Blue #483D8B ΔE 0.061
- Indigo Blue #3A18B1 ΔE 0.066
- Twilight Blue #0A437A ΔE 0.068
- Blue Blue #2242C7 ΔE 0.069
- Dusk Blue #26538D ΔE 0.073
Use #233B9E 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.