#51639A
Closest named color: Dusky Blue (#475F94). oklch(51% 0.09 269.3), rgb(81, 99, 154).
Aa
White text reads best on this color (5.83:1).
About this color
#51639A is a medium-dark, moderately saturated blue. In OKLCH its lightness is 51%, its chroma 0.090 and its hue 269°. Its hue sits on the cool side of the wheel. The nearest named color is Dusky Blue (#475F94), ΔE 0.020 away. White text reads best on it, at 5.83:1.
| Hue family | Blues |
| Lightness | medium-dark (51%) |
| Chroma | moderately saturated (0.090) |
| Temperature | cool |
| Nearest name | Dusky Blue (#475F94) |
| Black text | 3.60:1 |
| White text | 5.83:1 |
Values
| HEX | #51639A |
| RGB | rgb(81, 99, 154) |
| HSL | hsl(225, 31%, 46%) |
| OKLCH | oklch(51% 0.09 269.3) |
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 #51639A | 5.83:1 | AA | Lc -84.3 | Fine for body text |
| Black text on #51639A | 3.60:1 | AA large text | Lc 25.0 | Dividers and decoration only |
| #51639A text on white | 5.83:1 | AA | Lc 79.1 | Fine for body text |
| #51639A text on black | 3.60:1 | AA large text | Lc -22.7 | 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 700.
-
Step 50
50
#F4F5F9
oklch(97.1% 0.005 275)
-
Step 100
100
#E6EAF3
oklch(93.7% 0.013 266.7)
-
Step 200
200
#D2D9EA
oklch(88.5% 0.025 267.9)
-
Step 300
300
#B5C0DE
oklch(80.9% 0.044 269.5)
-
Step 400
400
#8F9FCD
oklch(70.7% 0.07 269.7)
-
Step 500
500
#7387C0
oklch(63.1% 0.089 268.9)
-
Step 600
600
#5C70AC
oklch(55.5% 0.097 269.1)
-
Step 700
700 (this color)
#51639A
oklch(51% 0.09 269.3)
-
Step 800
800
#3E4D78
oklch(42.8% 0.074 268.5)
-
Step 900
900
#354061
oklch(37.7% 0.059 269.4)
-
Step 950
950
#1F2639
oklch(27.1% 0.037 268.4)
#51639A 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) | #4F689C | 0.014 |
| Deuteranopia (no green cones) | #486299 | 0.012 |
| Tritanopia (no blue cones) | #356E77 | 0.080 |
| Achromatopsia (no color) | #656565 | 0.090 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #51639A
#51639A
oklch(51% 0.09 269.3)
- #7B631E
#7B631E
oklch(51% 0.091 89.1)
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 #51639A, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dusky Blue #475F94 ΔE 0.020
- French Blue #436BAD ΔE 0.035
- Denim #3B638C ΔE 0.036
- Denim Blue #3B5B92 ΔE 0.040
- Muted Blue #3B719F ΔE 0.043
- Flat Blue #3C73A8 ΔE 0.048
- Dull Blue #49759C ΔE 0.051
- Twilight #4E518B ΔE 0.053
Use #51639A 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.