#3378A6
Closest named color: Flat Blue (#3C73A8). oklch(55% 0.1 241.2), rgb(51, 120, 166).
Aa
White text reads best on this color (4.79:1).
About this color
#3378A6 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 55%, its chroma 0.100 and its hue 241°. Its hue sits on the cool side of the wheel. The nearest named color is Flat Blue (#3C73A8), ΔE 0.016 away. White text reads best on it, at 4.79:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | moderately saturated (0.100) |
| Temperature | cool |
| Nearest name | Flat Blue (#3C73A8) |
| Black text | 4.37:1 |
| White text | 4.79:1 |
Values
| HEX | #3378A6 |
| RGB | rgb(51, 120, 166) |
| HSL | hsl(204, 53%, 43%) |
| OKLCH | oklch(55% 0.1 241.2) |
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 #3378A6 | 4.79:1 | AA | Lc -78.5 | Fine for body text |
| Black text on #3378A6 | 4.37:1 | AA large text | Lc 31.1 | Non-text elements, placeholder text |
| #3378A6 text on white | 4.79:1 | AA | Lc 73.0 | Content text, not long reading |
| #3378A6 text on black | 4.37:1 | 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
#F2F6F9
oklch(97.1% 0.006 239.8)
-
Step 100
100
#E3EBF2
oklch(93.6% 0.013 244.3)
-
Step 200
200
#CBDCE8
oklch(88.5% 0.025 238.4)
-
Step 300
300
#A8C5DB
oklch(80.9% 0.044 240.9)
-
Step 400
400
#78A7CA
oklch(70.8% 0.072 241.2)
-
Step 500
500
#5390BC
oklch(63% 0.092 241.6)
-
Step 600
600 (this color)
#3378A6
oklch(55% 0.1 241.2)
-
Step 700
700
#276690
oklch(49% 0.093 241.6)
-
Step 800
800
#225475
oklch(42.8% 0.077 240.8)
-
Step 900
900
#21455E
oklch(37.6% 0.06 241.1)
-
Step 950
950
#142937
oklch(27% 0.038 239.4)
#3378A6 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) | #6378A8 | 0.051 |
| Deuteranopia (no green cones) | #536DA5 | 0.041 |
| Tritanopia (no blue cones) | #008388 | 0.069 |
| Achromatopsia (no color) | #727272 | 0.100 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3378A6
#3378A6
oklch(55% 0.1 241.2)
- #9B632E
#9B632E
oklch(55% 0.1 61.5)
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 #3378A6, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Flat Blue #3C73A8 ΔE 0.016
- Muted Blue #3B719F ΔE 0.021
- Nice Blue #107AB0 ΔE 0.021
- Dull Blue #49759C ΔE 0.023
- Cerulean #457B9D ΔE 0.024
- Stormy Blue #507B9C ΔE 0.033
- Ocean Blue #03719C ΔE 0.036
- Sea Blue #047495 ΔE 0.038
Use #3378A6 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.