#304E63
Closest named color: Dark Grey Blue (#29465B). oklch(41% 0.05 240.1), rgb(48, 78, 99).
Aa
White text reads best on this color (8.76:1).
About this color
#304E63 is a dark, muted blue. In OKLCH its lightness is 41%, its chroma 0.050 and its hue 240°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Grey Blue (#29465B), ΔE 0.029 away. White text reads best on it, at 8.76:1.
| Hue family | Blues |
| Lightness | dark (41%) |
| Chroma | muted (0.050) |
| Temperature | cool |
| Nearest name | Dark Grey Blue (#29465B) |
| Black text | 2.39:1 |
| White text | 8.76:1 |
Values
| HEX | #304E63 |
| RGB | rgb(48, 78, 99) |
| HSL | hsl(205, 35%, 29%) |
| OKLCH | oklch(41% 0.05 240.1) |
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 #304E63 | 8.76:1 | AAA | Lc -94.4 | Preferred for body text |
| Black text on #304E63 | 2.39:1 | Fails | Lc 14.0 | Not readable |
| #304E63 text on white | 8.76:1 | AAA | Lc 89.9 | Fine for body text |
| #304E63 text on black | 2.39:1 | Fails | Lc -12.3 | 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 800.
-
Step 50
50
#F3F6F8
oklch(97.1% 0.004 236.5)
-
Step 100
100
#E5EBEF
oklch(93.7% 0.008 236.6)
-
Step 200
200
#D0DBE3
oklch(88.5% 0.016 239.1)
-
Step 300
300
#B0C4D2
oklch(81% 0.029 238.3)
-
Step 400
400
#87A5BB
oklch(70.7% 0.046 240.1)
-
Step 500
500
#688FAB
oklch(63.2% 0.06 240.1)
-
Step 600
600
#4F7996
oklch(55.7% 0.065 239.6)
-
Step 700
700
#3F6580
oklch(49% 0.061 240.6)
-
Step 800
800 (this color)
#304E63
oklch(41% 0.05 240.1)
-
Step 900
900
#2E4555
oklch(37.8% 0.04 239.5)
-
Step 950
950
#1B2831
oklch(26.9% 0.025 239.1)
#304E63 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) | #454E64 | 0.028 |
| Deuteranopia (no green cones) | #3E4863 | 0.025 |
| Tritanopia (no blue cones) | #185355 | 0.040 |
| Achromatopsia (no color) | #4B4B4B | 0.050 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #304E63
#304E63
oklch(41% 0.05 240.1)
- #5F442E
#5F442E
oklch(41.1% 0.051 59.9)
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 #304E63, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Grey Blue #29465B ΔE 0.029
- Dark Slate Gray #2F4F4F ΔE 0.036
- Charcoal #264653 ΔE 0.037
- Deep Teal #00555A ΔE 0.043
- YInMn Blue #415A77 ΔE 0.052
- Dark Teal #014D4E ΔE 0.053
- Petrol #005F6A ΔE 0.055
- Deep Sea Blue #015482 ΔE 0.055
Use #304E63 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.