#02378C
Closest named color: Twilight Blue (#0A437A). oklch(36.7% 0.15 260.5), rgb(2, 55, 140).
Aa
White text reads best on this color (10.89:1).
About this color
#02378C is a dark, vivid blue. In OKLCH its lightness is 37%, its chroma 0.150 and its hue 260°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.048 away. White text reads best on it, at 10.89:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | vivid (0.150) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.92:1 |
| White text | 10.89:1 |
Values
| HEX | #02378C |
| RGB | rgb(2, 55, 140) |
| HSL | hsl(217, 97%, 28%) |
| OKLCH | oklch(36.7% 0.15 260.5) |
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 #02378C | 10.89:1 | AAA | Lc -98.4 | Preferred for body text |
| Black text on #02378C | 1.92:1 | Fails | Lc 9.5 | Not readable |
| #02378C text on white | 10.89:1 | AAA | Lc 94.4 | Preferred for body text |
| #02378C text on black | 1.92:1 | Fails | Lc -8.2 | 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
#DEEBFF
oklch(93.6% 0.031 258.9)
-
Step 200
200
#C4DAFF
oklch(88.4% 0.057 260.8)
-
Step 300
300
#9DC2FF
oklch(81% 0.096 260.2)
-
Step 400
400
#679FFF
oklch(70.7% 0.153 260.6)
-
Step 500
500
#3B83FF
oklch(63.1% 0.198 260.5)
-
Step 600
600
#0065F8
oklch(55.6% 0.233 260.5)
-
Step 700
700
#0055D2
oklch(49.1% 0.205 260.4)
-
Step 800
800
#0045AE
oklch(42.7% 0.178 260.4)
-
Step 900
900 (this color)
#02378C
oklch(36.7% 0.15 260.5)
-
Step 950
950
#072354
oklch(27% 0.096 260.7)
#02378C 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) | #00438F | 0.032 |
| Deuteranopia (no green cones) | #00378A | 0.004 |
| Tritanopia (no blue cones) | #004D5C | 0.113 |
| Achromatopsia (no color) | #3D3D3D | 0.151 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #02378C
#02378C
oklch(36.7% 0.15 260.5)
- #533A00
#533A00
oklch(36.7% 0.076 81.4)
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 #02378C, closest first.
No curated palette has a color within ΔE 0.04 of #02378C.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.048
- Cobalt #1E488F ΔE 0.053
- Sapphire #2138AB ΔE 0.057
- Marine Blue #01386A ΔE 0.059
- Royal #0C1793 ΔE 0.063
- Light Navy #155084 ΔE 0.076
- Marine #042E60 ΔE 0.079
- Cobalt Blue #030AA7 ΔE 0.080
Use #02378C 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.