#307A9C
Closest named color: Cerulean (#457B9D). oklch(54.8% 0.089 231.6), rgb(48, 122, 156).
Aa
White text reads best on this color (4.78:1).
About this color
#307A9C is a medium-dark, moderately saturated blue. In OKLCH its lightness is 55%, its chroma 0.089 and its hue 232°. Its hue sits on the cool side of the wheel. The nearest named color is Cerulean (#457B9D), ΔE 0.019 away. White text reads best on it, at 4.78:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | moderately saturated (0.089) |
| Temperature | cool |
| Nearest name | Cerulean (#457B9D) |
| Black text | 4.38:1 |
| White text | 4.78:1 |
Values
| HEX | #307A9C |
| RGB | rgb(48, 122, 156) |
| HSL | hsl(199, 53%, 40%) |
| OKLCH | oklch(54.8% 0.089 231.6) |
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 #307A9C | 4.78:1 | AA | Lc -78.4 | Fine for body text |
| Black text on #307A9C | 4.38:1 | AA large text | Lc 31.1 | Non-text elements, placeholder text |
| #307A9C text on white | 4.78:1 | AA | Lc 72.9 | Content text, not long reading |
| #307A9C text on black | 4.38:1 | AA large text | Lc -28.7 | Dividers and decoration only |
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 600.
-
Step 50
50
#F2F6F8
oklch(97.1% 0.005 228.8)
-
Step 100
100
#E3EBF0
oklch(93.5% 0.011 234.8)
-
Step 200
200
#CBDCE5
oklch(88.4% 0.022 230.6)
-
Step 300
300
#A7C6D6
oklch(80.9% 0.04 230.3)
-
Step 400
400
#77A8C2
oklch(70.6% 0.065 232)
-
Step 500
500
#5292B3
oklch(63% 0.082 232.6)
-
Step 600
600 (this color)
#307A9C
oklch(54.8% 0.089 231.6)
-
Step 700
700
#246987
oklch(49.2% 0.083 230.7)
-
Step 800
800
#20556E
oklch(42.6% 0.069 232.1)
-
Step 900
900
#204759
oklch(37.8% 0.054 230.4)
-
Step 950
950
#142934
oklch(26.9% 0.034 232.8)
#307A9C 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) | #69789E | 0.060 |
| Deuteranopia (no green cones) | #5A6E9C | 0.051 |
| Tritanopia (no blue cones) | #008385 | 0.055 |
| Achromatopsia (no color) | #727272 | 0.089 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #307A9C
#307A9C
oklch(54.8% 0.089 231.6)
- #9A613E
#9A613E
oklch(54.8% 0.089 51.5)
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 #307A9C, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cerulean #457B9D ΔE 0.019
- Dull Blue #49759C ΔE 0.024
- Ocean #017B92 ΔE 0.027
- Muted Blue #3B719F ΔE 0.029
- Stormy Blue #507B9C ΔE 0.030
- Sea Blue #047495 ΔE 0.030
- Flat Blue #3C73A8 ΔE 0.033
- Nice Blue #107AB0 ΔE 0.034
Use #307A9C 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.