#00438B
Closest named color: Cobalt (#1E488F). oklch(39.2% 0.134 256), rgb(0, 67, 139).
Aa
White text reads best on this color (9.65:1).
About this color
#00438B is a dark, moderately saturated blue. In OKLCH its lightness is 39%, its chroma 0.134 and its hue 256°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.025 away. White text reads best on it, at 9.65:1.
| Hue family | Blues |
| Lightness | dark (39%) |
| Chroma | moderately saturated (0.134) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.17:1 |
| White text | 9.65:1 |
Values
| HEX | #00438B |
| RGB | rgb(0, 67, 139) |
| HSL | hsl(211, 100%, 27%) |
| OKLCH | oklch(39.2% 0.134 256) |
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 #00438B | 9.65:1 | AAA | Lc -95.9 | Preferred for body text |
| Black text on #00438B | 2.17:1 | Fails | Lc 12.3 | Not readable |
| #00438B text on white | 9.65:1 | AAA | Lc 91.7 | Preferred for body text |
| #00438B text on black | 2.17:1 | Fails | Lc -10.7 | 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
#DEEBFE
oklch(93.6% 0.029 257.8)
-
Step 200
200
#C2DBFE
oklch(88.4% 0.055 256.8)
-
Step 300
300
#97C3FF
oklch(80.8% 0.098 256.3)
-
Step 400
400
#5BA2FF
oklch(70.8% 0.155 255.9)
-
Step 500
500
#1D86FF
oklch(63.1% 0.201 256)
-
Step 600
600
#006FDF
oklch(55.6% 0.191 256.1)
-
Step 700
700
#005DBD
oklch(49.1% 0.169 256.1)
-
Step 800
800
#004C9C
oklch(42.7% 0.146 256)
-
Step 900
900 (this color)
#00438B
oklch(39.2% 0.134 256)
-
Step 950
950
#04254F
oklch(27% 0.086 256.5)
#00438B 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) | #124B8E | 0.026 |
| Deuteranopia (no green cones) | #003F8A | 0.011 |
| Tritanopia (no blue cones) | #005560 | 0.101 |
| Achromatopsia (no color) | #454545 | 0.134 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #00438B
#00438B
oklch(39.2% 0.134 256)
- #5E3E00
#5E3E00
oklch(39.1% 0.082 76)
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 #00438B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.025
- Twilight Blue #0A437A ΔE 0.029
- Light Navy #155084 ΔE 0.044
- Deep Sea Blue #015482 ΔE 0.055
- Dusk Blue #26538D ΔE 0.056
- Sapphire #2138AB ΔE 0.062
- Marine Blue #01386A ΔE 0.062
- Blueberry #464196 ΔE 0.070
Use #00438B 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.