#3F77AC
Closest named color: Flat Blue (#3C73A8). oklch(55.5% 0.102 249), rgb(63, 119, 172).
Aa
White text reads best on this color (4.72:1).
About this color
#3F77AC is a medium-dark, moderately saturated blue. In OKLCH its lightness is 56%, its chroma 0.102 and its hue 249°. Its hue sits on the cool side of the wheel. The nearest named color is Flat Blue (#3C73A8), ΔE 0.013 away. White text reads best on it, at 4.72:1.
| Hue family | Blues |
| Lightness | medium-dark (56%) |
| Chroma | moderately saturated (0.102) |
| Temperature | cool |
| Nearest name | Flat Blue (#3C73A8) |
| Black text | 4.44:1 |
| White text | 4.72:1 |
Values
| HEX | #3F77AC |
| RGB | rgb(63, 119, 172) |
| HSL | hsl(209, 46%, 46%) |
| OKLCH | oklch(55.5% 0.102 249) |
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 #3F77AC | 4.72:1 | AA | Lc -78.0 | Fine for body text |
| Black text on #3F77AC | 4.44:1 | AA large text | Lc 31.5 | Non-text elements, placeholder text |
| #3F77AC text on white | 4.72:1 | AA | Lc 72.6 | Content text, not long reading |
| #3F77AC text on black | 4.44:1 | AA large text | Lc -29.1 | 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 600.
-
Step 50
50
#F2F6F9
oklch(97.1% 0.006 239.8)
-
Step 100
100
#E3EBF3
oklch(93.6% 0.014 248)
-
Step 200
200
#CDDBEA
oklch(88.5% 0.026 250)
-
Step 300
300
#AAC4DE
oklch(80.9% 0.046 248.4)
-
Step 400
400
#7DA5CD
oklch(70.8% 0.073 248.9)
-
Step 500
500
#5B8EC0
oklch(63.2% 0.094 249)
-
Step 600
600 (this color)
#3F77AC
oklch(55.5% 0.102 249)
-
Step 700
700
#316494
oklch(49.1% 0.095 249.1)
-
Step 800
800
#295278
oklch(42.7% 0.079 248.5)
-
Step 900
900
#264461
oklch(37.7% 0.062 249)
-
Step 950
950
#172839
oklch(27.1% 0.039 249.5)
#3F77AC 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) | #6079AE | 0.038 |
| Deuteranopia (no green cones) | #516FAB | 0.027 |
| Tritanopia (no blue cones) | #00838A | 0.079 |
| Achromatopsia (no color) | #737373 | 0.102 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F77AC
#3F77AC
oklch(55.5% 0.102 249)
- #996727
#996727
oklch(55.5% 0.101 69.2)
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 #3F77AC, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Flat Blue #3C73A8 ΔE 0.013
- Muted Blue #3B719F ΔE 0.025
- Dull Blue #49759C ΔE 0.025
- Nice Blue #107AB0 ΔE 0.026
- Windows Blue #3778BF ΔE 0.030
- Cerulean #457B9D ΔE 0.030
- Steel Blue #4682B4 ΔE 0.033
- French Blue #436BAD ΔE 0.035
Use #3F77AC 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.