#637DC2
Closest named color: Cool Blue (#4984B8). oklch(60% 0.11 267.4), rgb(99, 125, 194).
Aa
Black text reads best on this color (5.24:1).
About this color
#637DC2 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 60%, its chroma 0.110 and its hue 267°. Its hue sits on the cool side of the wheel. The nearest named color is Cool Blue (#4984B8), ΔE 0.038 away. Black text reads best on it, at 5.24:1.
| Hue family | Blues |
| Lightness | medium-dark (60%) |
| Chroma | moderately saturated (0.110) |
| Temperature | cool |
| Nearest name | Cool Blue (#4984B8) |
| Black text | 5.24:1 |
| White text | 4.00:1 |
Values
| HEX | #637DC2 |
| RGB | rgb(99, 125, 194) |
| HSL | hsl(224, 44%, 57%) |
| OKLCH | oklch(60% 0.11 267.4) |
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 #637DC2 | 4.00:1 | AA large text | Lc -72.8 | Content text, not long reading |
| Black text on #637DC2 | 5.24:1 | AA | Lc 36.8 | Non-text elements, placeholder text |
| #637DC2 text on white | 4.00:1 | AA large text | Lc 67.2 | Content text, not long reading |
| #637DC2 text on black | 5.24:1 | AA | Lc -34.4 | Non-text elements, placeholder text |
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 500.
-
Step 50
50
#F3F5FA
oklch(97% 0.007 268.5)
-
Step 100
100
#E5EAF5
oklch(93.6% 0.016 266.3)
-
Step 200
200
#D0D9EE
oklch(88.5% 0.031 267.2)
-
Step 300
300
#B1C0E4
oklch(80.8% 0.054 267.4)
-
Step 400
400
#899FD7
oklch(70.7% 0.086 267.6)
-
Step 500
500 (this color)
#637DC2
oklch(60% 0.11 267.4)
-
Step 600
600
#546FB9
oklch(55.5% 0.12 267.3)
-
Step 700
700
#455DA0
oklch(49.2% 0.111 267.4)
-
Step 800
800
#394C81
oklch(42.7% 0.091 267.6)
-
Step 900
900
#314068
oklch(37.8% 0.071 267.4)
-
Step 950
950
#1D253D
oklch(26.9% 0.046 269.1)
#637DC2 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) | #6384C5 | 0.019 |
| Deuteranopia (no green cones) | #597BC0 | 0.014 |
| Tritanopia (no blue cones) | #3C8C96 | 0.100 |
| Achromatopsia (no color) | #7F7F7F | 0.110 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #637DC2
#637DC2
oklch(60% 0.11 267.4)
- #9C7B22
#9C7B22
oklch(59.9% 0.11 87.2)
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 #637DC2, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cool Blue #4984B8 ΔE 0.038
- Steel Blue #4682B4 ΔE 0.042
- Off Blue #5684AE ΔE 0.044
- Faded Blue #658CBB ΔE 0.046
- Dusty Blue #5A86AD ΔE 0.047
- Windows Blue #3778BF ΔE 0.050
- Water Blue #0E87CC ΔE 0.061
- Soft Blue #6488EA ΔE 0.063
Use #637DC2 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.