#303B59
Closest named color: Dark Blue Grey (#1F3B4D). oklch(35.7% 0.054 268.2), rgb(48, 59, 89).
Aa
White text reads best on this color (11.07:1).
About this color
#303B59 is a dark, muted blue. In OKLCH its lightness is 36%, its chroma 0.054 and its hue 268°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Blue Grey (#1F3B4D), ΔE 0.032 away. White text reads best on it, at 11.07:1.
| Hue family | Blues |
| Lightness | dark (36%) |
| Chroma | muted (0.054) |
| Temperature | cool |
| Nearest name | Dark Blue Grey (#1F3B4D) |
| Black text | 1.89:1 |
| White text | 11.07:1 |
Values
| HEX | #303B59 |
| RGB | rgb(48, 59, 89) |
| HSL | hsl(224, 30%, 27%) |
| OKLCH | oklch(35.7% 0.054 268.2) |
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 #303B59 | 11.07:1 | AAA | Lc -99.4 | Preferred for body text |
| Black text on #303B59 | 1.89:1 | Fails | Lc 8.3 | Not readable |
| #303B59 text on white | 11.07:1 | AAA | Lc 95.6 | Preferred for body text |
| #303B59 text on black | 1.89:1 | Fails | Lc 0.0 | 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
#F4F5F9
oklch(97.1% 0.005 275)
-
Step 100
100
#E6EAF2
oklch(93.6% 0.012 264.5)
-
Step 200
200
#D3D9E9
oklch(88.6% 0.023 269.4)
-
Step 300
300
#B5C0DC
oklch(80.8% 0.041 268.5)
-
Step 400
400
#8FA0CA
oklch(70.8% 0.065 267.6)
-
Step 500
500
#7488BD
oklch(63.2% 0.084 268.1)
-
Step 600
600
#5D71A9
oklch(55.7% 0.091 268.4)
-
Step 700
700
#4C5E91
oklch(49% 0.085 268.4)
-
Step 800
800
#3F4D76
oklch(42.7% 0.071 268.9)
-
Step 900
900 (this color)
#303B59
oklch(35.7% 0.054 268.2)
-
Step 950
950
#1F2638
oklch(27.1% 0.035 267.7)
#303B59 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) | #303E5A | 0.009 |
| Deuteranopia (no green cones) | #2D3A58 | 0.006 |
| Tritanopia (no blue cones) | #224146 | 0.048 |
| Achromatopsia (no color) | #3C3C3C | 0.054 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #303B59
#303B59
oklch(35.7% 0.054 268.2)
- #483A18
#483A18
oklch(35.5% 0.054 87)
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 #303B59, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Blue Grey #1F3B4D ΔE 0.032
- Prussian Blue #1D3557 ΔE 0.034
- Dark Grey Blue #29465B ΔE 0.035
- Charcoal #264653 ΔE 0.041
- Onyx #343A40 ΔE 0.044
- Gunmetal #293241 ΔE 0.048
- Midnight Green #073B4C ΔE 0.049
- Charcoal Grey #3C4142 ΔE 0.053
Use #303B59 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.