#303F87
Closest named color: Cobalt (#1E488F). oklch(39.7% 0.121 271), rgb(48, 63, 135).
Aa
White text reads best on this color (9.60:1).
About this color
#303F87 is a dark, moderately saturated blue. In OKLCH its lightness is 40%, its chroma 0.121 and its hue 271°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.029 away. White text reads best on it, at 9.60:1.
| Hue family | Blues |
| Lightness | dark (40%) |
| Chroma | moderately saturated (0.121) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.18:1 |
| White text | 9.60:1 |
Values
| HEX | #303F87 |
| RGB | rgb(48, 63, 135) |
| HSL | hsl(230, 48%, 36%) |
| OKLCH | oklch(39.7% 0.121 271) |
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 #303F87 | 9.60:1 | AAA | Lc -96.2 | Preferred for body text |
| Black text on #303F87 | 2.18:1 | Fails | Lc 12.0 | Not readable |
| #303F87 text on white | 9.60:1 | AAA | Lc 92.0 | Preferred for body text |
| #303F87 text on black | 2.18:1 | Fails | Lc -10.4 | 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
#F2F5FE
oklch(97% 0.012 271.3)
-
Step 100
100
#E3E9FC
oklch(93.5% 0.027 271.9)
-
Step 200
200
#CCD8FB
oklch(88.4% 0.05 270.4)
-
Step 300
300
#ABBEFC
oklch(80.9% 0.09 271.1)
-
Step 400
400
#8099FB
oklch(70.6% 0.146 271.4)
-
Step 500
500
#627DF8
oklch(63.2% 0.185 270.9)
-
Step 600
600
#4B62E7
oklch(55.6% 0.202 270.9)
-
Step 700
700
#3D50C9
oklch(49.1% 0.188 270.9)
-
Step 800
800
#3242A2
oklch(42.6% 0.155 271)
-
Step 900
900 (this color)
#303F87
oklch(39.7% 0.121 271)
-
Step 950
950
#19224B
oklch(26.9% 0.077 271.1)
#303F87 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) | #14498A | 0.034 |
| Deuteranopia (no green cones) | #004186 | 0.037 |
| Tritanopia (no blue cones) | #00505C | 0.104 |
| Achromatopsia (no color) | #454545 | 0.121 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #303F87
#303F87
oklch(39.7% 0.121 271)
- #574400
#574400
oklch(39.6% 0.081 90.6)
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 #303F87, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.029
- Dark Slate Blue #483D8B ΔE 0.037
- Twilight Blue #0A437A ΔE 0.042
- Blueberry #464196 ΔE 0.042
- Light Navy #155084 ΔE 0.052
- Dusk Blue #26538D ΔE 0.055
- Sapphire #2138AB ΔE 0.064
- Deep Sea Blue #015482 ΔE 0.066
Use #303F87 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.