#0370A3
Closest named color: Ocean Blue (#03719C). oklch(51.8% 0.116 238.8), rgb(3, 112, 163).
Aa
White text reads best on this color (5.45:1).
About this color
#0370A3 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 52%, its chroma 0.116 and its hue 239°. Its hue sits on the cool side of the wheel. The nearest named color is Ocean Blue (#03719C), ΔE 0.012 away. White text reads best on it, at 5.45:1.
| Hue family | Blues |
| Lightness | medium-dark (52%) |
| Chroma | moderately saturated (0.116) |
| Temperature | cool |
| Nearest name | Ocean Blue (#03719C) |
| Black text | 3.85:1 |
| White text | 5.45:1 |
Values
| HEX | #0370A3 |
| RGB | rgb(3, 112, 163) |
| HSL | hsl(199, 96%, 33%) |
| OKLCH | oklch(51.8% 0.116 238.8) |
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 #0370A3 | 5.45:1 | AA | Lc -82.0 | Fine for body text |
| Black text on #0370A3 | 3.85:1 | AA large text | Lc 27.4 | Dividers and decoration only |
| #0370A3 text on white | 5.45:1 | AA | Lc 76.6 | Fine for body text |
| #0370A3 text on black | 3.85:1 | AA large text | Lc -25.1 | 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 700.
-
Step 50
50
#F1F6FA
oklch(97.1% 0.008 241.7)
-
Step 100
100
#E0ECF4
oklch(93.6% 0.017 236.7)
-
Step 200
200
#C7DDEC
oklch(88.6% 0.031 237.6)
-
Step 300
300
#A0C6E1
oklch(80.8% 0.056 239.3)
-
Step 400
400
#69A9D2
oklch(70.8% 0.089 238)
-
Step 500
500
#3B92C7
oklch(63.1% 0.115 239.2)
-
Step 600
600
#027CB3
oklch(55.7% 0.124 238.3)
-
Step 700
700 (this color)
#0370A3
oklch(51.8% 0.116 238.8)
-
Step 800
800
#00557D
oklch(42.7% 0.096 238.5)
-
Step 900
900
#114665
oklch(37.6% 0.075 239.6)
-
Step 950
950
#0D293B
oklch(26.9% 0.047 240.1)
#0370A3 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) | #5771A5 | 0.061 |
| Deuteranopia (no green cones) | #4364A2 | 0.047 |
| Tritanopia (no blue cones) | #007D82 | 0.075 |
| Achromatopsia (no color) | #696969 | 0.116 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #0370A3
#0370A3
oklch(51.8% 0.116 238.8)
- #985512
#985512
oklch(51.8% 0.115 58.7)
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 #0370A3, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Ocean Blue #03719C ΔE 0.012
- Sea Blue #047495 ΔE 0.028
- Muted Blue #3B719F ΔE 0.030
- Peacock Blue #016795 ΔE 0.032
- Nice Blue #107AB0 ΔE 0.034
- Flat Blue #3C73A8 ΔE 0.034
- Mid Blue #276AB3 ΔE 0.036
- French Blue #436BAD ΔE 0.044
Use #0370A3 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.