#637AFF
Closest named color: Cornflower (#6A79F7). oklch(63.2% 0.198 272.1), rgb(99, 122, 255).
Aa
Black text reads best on this color (5.75:1).
About this color
#637AFF is a medium-light, vivid blue. In OKLCH its lightness is 63%, its chroma 0.198 and its hue 272°. Its hue sits on the cool side of the wheel. The nearest named color is Cornflower (#6A79F7), ΔE 0.014 away. Black text reads best on it, at 5.75:1.
| Hue family | Blues |
| Lightness | medium-light (63%) |
| Chroma | vivid (0.198) |
| Temperature | cool |
| Nearest name | Cornflower (#6A79F7) |
| Black text | 5.75:1 |
| White text | 3.64:1 |
Values
| HEX | #637AFF |
| RGB | rgb(99, 122, 255) |
| HSL | hsl(231, 100%, 69%) |
| OKLCH | oklch(63.2% 0.198 272.1) |
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 #637AFF | 3.64:1 | AA large text | Lc -69.2 | Content text, not long reading |
| Black text on #637AFF | 5.75:1 | AA | Lc 40.4 | Non-text elements, placeholder text |
| #637AFF text on white | 3.64:1 | AA large text | Lc 63.7 | Content text, not long reading |
| #637AFF text on black | 5.75:1 | AA | Lc -38.0 | 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
#F2F5FF
oklch(97.1% 0.014 272.7)
-
Step 100
100
#E3E9FD
oklch(93.5% 0.028 272.5)
-
Step 200
200
#CCD8FE
oklch(88.5% 0.054 271.5)
-
Step 300
300
#ABBDFF
oklch(80.9% 0.096 272.3)
-
Step 400
400
#8098FF
oklch(70.7% 0.153 272.1)
-
Step 500
500 (this color)
#637AFF
oklch(63.2% 0.198 272.1)
-
Step 600
600
#4D5EEE
oklch(55.6% 0.215 272.2)
-
Step 700
700
#3F4CCF
oklch(49% 0.2 272.2)
-
Step 800
800
#3340A7
oklch(42.7% 0.165 271.9)
-
Step 900
900
#2C3885
oklch(37.8% 0.129 272)
-
Step 950
950
#19214E
oklch(26.9% 0.083 272.1)
#637AFF 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) | #268DFF | 0.061 |
| Deuteranopia (no green cones) | #007FFC | 0.062 |
| Tritanopia (no blue cones) | #0099B1 | 0.168 |
| Achromatopsia (no color) | #868686 | 0.198 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #637AFF
#637AFF
oklch(63.2% 0.198 272.1)
- #A68600
#A68600
oklch(63.2% 0.129 91.9)
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 #637AFF, closest first.
No curated palette has a color within ΔE 0.04 of #637AFF.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cornflower #6A79F7 ΔE 0.014
- Soft Blue #6488EA ΔE 0.050
- Medium Slate Blue #7B68EE ΔE 0.053
- Clear Blue #247AFD ΔE 0.054
- Periwinkle #8E82FE ΔE 0.063
- Dodger Blue #1E90FF ΔE 0.067
- Lavender Blue #8B88F8 ΔE 0.068
- Dark Sky Blue #448EE4 ΔE 0.073
Use #637AFF 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.