#3978A2
Closest named color: Dull Blue (#49759C). oklch(55% 0.092 240.5), rgb(57, 120, 162).
Aa
White text reads best on this color (4.79:1).
About this color
#3978A2 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 55%, its chroma 0.092 and its hue 241°. Its hue sits on the cool side of the wheel. The nearest named color is Dull Blue (#49759C), ΔE 0.017 away. White text reads best on it, at 4.79:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | moderately saturated (0.092) |
| Temperature | cool |
| Nearest name | Dull Blue (#49759C) |
| Black text | 4.38:1 |
| White text | 4.79:1 |
Values
| HEX | #3978A2 |
| RGB | rgb(57, 120, 162) |
| HSL | hsl(204, 48%, 43%) |
| OKLCH | oklch(55% 0.092 240.5) |
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 #3978A2 | 4.79:1 | AA | Lc -78.5 | Fine for body text |
| Black text on #3978A2 | 4.38:1 | AA large text | Lc 31.0 | Non-text elements, placeholder text |
| #3978A2 text on white | 4.79:1 | AA | Lc 73.0 | Content text, not long reading |
| #3978A2 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
#F2F6F9
oklch(97.1% 0.006 239.8)
-
Step 100
100
#E3EBF1
oklch(93.6% 0.012 239.9)
-
Step 200
200
#CCDCE7
oklch(88.6% 0.023 237.7)
-
Step 300
300
#A9C5D9
oklch(80.9% 0.041 239.1)
-
Step 400
400
#7BA7C6
oklch(70.8% 0.066 239.6)
-
Step 500
500
#5890B8
oklch(63.1% 0.085 241)
-
Step 600
600 (this color)
#3978A2
oklch(55% 0.092 240.5)
-
Step 700
700
#2D668C
oklch(49% 0.085 240.8)
-
Step 800
800
#265472
oklch(42.8% 0.071 239.9)
-
Step 900
900
#24455C
oklch(37.6% 0.055 240.8)
-
Step 950
950
#162936
oklch(27.1% 0.035 239.7)
#3978A2 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) | #6578A4 | 0.049 |
| Deuteranopia (no green cones) | #576EA1 | 0.039 |
| Tritanopia (no blue cones) | #008286 | 0.066 |
| Achromatopsia (no color) | #727272 | 0.092 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3978A2
#3978A2
oklch(55% 0.092 240.5)
- #986435
#986435
oklch(54.9% 0.092 61.1)
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 #3978A2, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dull Blue #49759C ΔE 0.017
- Cerulean #457B9D ΔE 0.018
- Flat Blue #3C73A8 ΔE 0.019
- Muted Blue #3B719F ΔE 0.020
- Stormy Blue #507B9C ΔE 0.027
- Nice Blue #107AB0 ΔE 0.028
- Metallic Blue #4F738E ΔE 0.035
- Sea Blue #047495 ΔE 0.038
Use #3978A2 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.