#133B8A
Closest named color: Twilight Blue (#0A437A). oklch(37.7% 0.139 262), rgb(19, 59, 138).
Aa
White text reads best on this color (10.39:1).
About this color
#133B8A is a dark, moderately saturated blue. In OKLCH its lightness is 38%, its chroma 0.139 and its hue 262°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.037 away. White text reads best on it, at 10.39:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | moderately saturated (0.139) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.02:1 |
| White text | 10.39:1 |
Values
| HEX | #133B8A |
| RGB | rgb(19, 59, 138) |
| HSL | hsl(220, 76%, 31%) |
| OKLCH | oklch(37.7% 0.139 262) |
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 #133B8A | 10.39:1 | AAA | Lc -97.6 | Preferred for body text |
| Black text on #133B8A | 2.02:1 | Fails | Lc 10.4 | Not readable |
| #133B8A text on white | 10.39:1 | AAA | Lc 93.6 | Preferred for body text |
| #133B8A text on black | 2.02:1 | Fails | Lc -9.0 | 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
#F0F6FF
oklch(97.1% 0.014 258.3)
-
Step 100
100
#DFEAFF
oklch(93.5% 0.031 263.5)
-
Step 200
200
#C5DAFF
oklch(88.5% 0.056 261.8)
-
Step 300
300
#9FC1FF
oklch(80.9% 0.096 262.2)
-
Step 400
400
#6B9EFF
oklch(70.7% 0.153 262.2)
-
Step 500
500
#4282FF
oklch(63.2% 0.198 262)
-
Step 600
600
#1864F8
oklch(55.6% 0.232 262)
-
Step 700
700
#0A51D8
oklch(49% 0.216 262.1)
-
Step 800
800
#0D44AE
oklch(42.7% 0.178 261.9)
-
Step 900
900 (this color)
#133B8A
oklch(37.7% 0.139 262)
-
Step 950
950
#0C2351
oklch(26.9% 0.089 262.2)
#133B8A 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) | #00458D | 0.027 |
| Deuteranopia (no green cones) | #003B88 | 0.011 |
| Tritanopia (no blue cones) | #004F5C | 0.108 |
| Achromatopsia (no color) | #404040 | 0.140 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #133B8A
#133B8A
oklch(37.7% 0.139 262)
- #563D00
#563D00
oklch(37.8% 0.078 82.4)
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 #133B8A, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.037
- Cobalt #1E488F ΔE 0.039
- Sapphire #2138AB ΔE 0.056
- Marine Blue #01386A ΔE 0.057
- Light Navy #155084 ΔE 0.063
- Dark Slate Blue #483D8B ΔE 0.068
- Blueberry #464196 ΔE 0.070
- Dusk Blue #26538D ΔE 0.073
Use #133B8A 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.