#637ADD
Closest named color: Soft Blue (#6488EA). oklch(60.9% 0.152 271.4), rgb(99, 122, 221).
Aa
Black text reads best on this color (5.35:1).
About this color
#637ADD is a medium-dark, vivid blue. In OKLCH its lightness is 61%, its chroma 0.152 and its hue 271°. Its hue sits on the cool side of the wheel. The nearest named color is Soft Blue (#6488EA), ΔE 0.039 away. Black text reads best on it, at 5.35:1.
| Hue family | Blues |
| Lightness | medium-dark (61%) |
| Chroma | vivid (0.152) |
| Temperature | cool |
| Nearest name | Soft Blue (#6488EA) |
| Black text | 5.35:1 |
| White text | 3.91:1 |
Values
| HEX | #637ADD |
| RGB | rgb(99, 122, 221) |
| HSL | hsl(229, 64%, 63%) |
| OKLCH | oklch(60.9% 0.152 271.4) |
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 #637ADD | 3.91:1 | AA large text | Lc -71.9 | Content text, not long reading |
| Black text on #637ADD | 5.35:1 | AA | Lc 37.7 | Non-text elements, placeholder text |
| #637ADD text on white | 3.91:1 | AA large text | Lc 66.4 | Content text, not long reading |
| #637ADD text on black | 5.35:1 | AA | Lc -35.3 | 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
#F3F5FC
oklch(97.1% 0.01 273.4)
-
Step 100
100
#E4E9F9
oklch(93.5% 0.022 272.1)
-
Step 200
200
#CFD8F5
oklch(88.4% 0.041 271.9)
-
Step 300
300
#AFBFF1
oklch(81% 0.073 270.9)
-
Step 400
400
#869CEB
oklch(70.8% 0.119 271.3)
-
Step 500
500 (this color)
#637ADD
oklch(60.9% 0.152 271.4)
-
Step 600
600
#5268D2
oklch(55.6% 0.164 271.3)
-
Step 700
700
#4356B6
oklch(49.1% 0.153 271.3)
-
Step 800
800
#374794
oklch(42.8% 0.127 271.2)
-
Step 900
900
#2F3C76
oklch(37.7% 0.1 271.4)
-
Step 950
950
#1C2445
oklch(27.1% 0.062 271.5)
#637ADD 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) | #4E86E1 | 0.035 |
| Deuteranopia (no green cones) | #3E7CDB | 0.038 |
| Tritanopia (no blue cones) | #1D90A1 | 0.135 |
| Achromatopsia (no color) | #818181 | 0.152 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #637ADD
#637ADD
oklch(60.9% 0.152 271.4)
- #9E7F00
#9E7F00
oklch(60.8% 0.124 91.5)
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 #637ADD, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Soft Blue #6488EA ΔE 0.039
- Cornflower #6A79F7 ΔE 0.041
- Dark Sky Blue #448EE4 ΔE 0.055
- Medium Slate Blue #7B68EE ΔE 0.060
- Royal Blue #4169E1 ΔE 0.063
- Dark Periwinkle #665FD1 ΔE 0.067
- Windows Blue #3778BF ΔE 0.067
- Medium Purple #9370DB ΔE 0.070
Use #637ADD 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.