#636DBC
Closest named color: French Blue (#436BAD). oklch(56.3% 0.122 276.3), rgb(99, 109, 188).
Aa
White text reads best on this color (4.72:1).
About this color
#636DBC is a medium-dark, moderately saturated blue. In OKLCH its lightness is 56%, its chroma 0.122 and its hue 276°. Its hue sits on the cool side of the wheel. The nearest named color is French Blue (#436BAD), ΔE 0.048 away. White text reads best on it, at 4.72:1.
| Hue family | Blues |
| Lightness | medium-dark (56%) |
| Chroma | moderately saturated (0.122) |
| Temperature | cool |
| Nearest name | French Blue (#436BAD) |
| Black text | 4.44:1 |
| White text | 4.72:1 |
Values
| HEX | #636DBC |
| RGB | rgb(99, 109, 188) |
| HSL | hsl(233, 40%, 56%) |
| OKLCH | oklch(56.3% 0.122 276.3) |
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 #636DBC | 4.72:1 | AA | Lc -78.1 | Fine for body text |
| Black text on #636DBC | 4.44:1 | AA large text | Lc 31.4 | Non-text elements, placeholder text |
| #636DBC text on white | 4.72:1 | AA | Lc 72.7 | Content text, not long reading |
| #636DBC text on black | 4.44:1 | AA large text | Lc -29.0 | 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
#F4F5FA
oklch(97.1% 0.007 277.2)
-
Step 100
100
#E7E9F5
oklch(93.6% 0.016 278.5)
-
Step 200
200
#D3D8EE
oklch(88.5% 0.031 275.6)
-
Step 300
300
#B7BEE5
oklch(80.9% 0.056 277.1)
-
Step 400
400
#929CD8
oklch(70.7% 0.089 276.6)
-
Step 500
500
#7883CD
oklch(63.2% 0.112 276.3)
-
Step 600
600 (this color)
#636DBC
oklch(56.3% 0.122 276.3)
-
Step 700
700
#5059A0
oklch(49.1% 0.113 276)
-
Step 800
800
#424982
oklch(42.8% 0.094 276.4)
-
Step 900
900
#373D68
oklch(37.6% 0.074 276.2)
-
Step 950
950
#20243D
oklch(26.9% 0.047 275.9)
#636DBC 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) | #4E77BF | 0.034 |
| Deuteranopia (no green cones) | #4770BA | 0.034 |
| Tritanopia (no blue cones) | #427D8B | 0.107 |
| Achromatopsia (no color) | #737373 | 0.122 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #636DBC
#636DBC
oklch(56.3% 0.122 276.3)
- #897400
#897400
oklch(56.2% 0.116 96.4)
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 #636DBC, closest first.
No curated palette has a color within ΔE 0.04 of #636DBC.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- French Blue #436BAD ΔE 0.048
- Dark Periwinkle #665FD1 ΔE 0.052
- Windows Blue #3778BF ΔE 0.052
- Iris #6258C4 ΔE 0.057
- Slate Blue #6A5ACD ΔE 0.058
- Flat Blue #3C73A8 ΔE 0.059
- Light Indigo #6D5ACF ΔE 0.060
- Steel Blue #4682B4 ΔE 0.067
Use #636DBC 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.