#637FF7
Closest named color: Cornflower (#6A79F7). oklch(63.6% 0.181 270.6), rgb(99, 127, 247).
Aa
Black text reads best on this color (5.90:1).
About this color
#637FF7 is a medium-light, vivid blue. In OKLCH its lightness is 64%, its chroma 0.181 and its hue 271°. Its hue sits on the cool side of the wheel. The nearest named color is Cornflower (#6A79F7), ΔE 0.016 away. Black text reads best on it, at 5.90:1.
| Hue family | Blues |
| Lightness | medium-light (64%) |
| Chroma | vivid (0.181) |
| Temperature | cool |
| Nearest name | Cornflower (#6A79F7) |
| Black text | 5.90:1 |
| White text | 3.55:1 |
Values
| HEX | #637FF7 |
| RGB | rgb(99, 127, 247) |
| HSL | hsl(229, 90%, 68%) |
| OKLCH | oklch(63.6% 0.181 270.6) |
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 #637FF7 | 3.55:1 | AA large text | Lc -68.3 | Content text, not long reading |
| Black text on #637FF7 | 5.90:1 | AA | Lc 41.2 | Non-text elements, placeholder text |
| #637FF7 text on white | 3.55:1 | AA large text | Lc 62.8 | Content text, not long reading |
| #637FF7 text on black | 5.90:1 | AA | Lc -38.9 | 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
#F2F5FE
oklch(97% 0.012 271.3)
-
Step 100
100
#E3E9FC
oklch(93.5% 0.027 271.9)
-
Step 200
200
#CDD8FB
oklch(88.5% 0.05 271.6)
-
Step 300
300
#ABBEFB
oklch(80.9% 0.089 270.9)
-
Step 400
400
#809AF9
oklch(70.7% 0.142 270.8)
-
Step 500
500 (this color)
#637FF7
oklch(63.6% 0.181 270.6)
-
Step 600
600
#4B63E4
oklch(55.6% 0.197 270.7)
-
Step 700
700
#3D51C6
oklch(49.1% 0.183 270.7)
-
Step 800
800
#3243A0
oklch(42.6% 0.151 270.7)
-
Step 900
900
#2B3A7F
oklch(37.7% 0.118 270.6)
-
Step 950
950
#19234A
oklch(27.1% 0.073 270.1)
#637FF7 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) | #408FFB | 0.047 |
| Deuteranopia (no green cones) | #2382F4 | 0.052 |
| Tritanopia (no blue cones) | #009AAF | 0.156 |
| Achromatopsia (no color) | #888888 | 0.181 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #637FF7
#637FF7
oklch(63.6% 0.181 270.6)
- #A98600
#A98600
oklch(63.5% 0.13 90.2)
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 #637FF7, closest first.
No curated palette has a color within ΔE 0.04 of #637FF7.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cornflower #6A79F7 ΔE 0.016
- Soft Blue #6488EA ΔE 0.032
- Clear Blue #247AFD ΔE 0.057
- Dark Sky Blue #448EE4 ΔE 0.058
- Medium Slate Blue #7B68EE ΔE 0.059
- Dodger Blue #1E90FF ΔE 0.059
- Lavender Blue #8B88F8 ΔE 0.060
- Periwinkle #8E82FE ΔE 0.060
Use #637FF7 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.