#638FF0
Closest named color: Cornflower Blue (#6495ED). oklch(66.3% 0.152 264.3), rgb(99, 143, 240).
Aa
Black text reads best on this color (6.71:1).
About this color
#638FF0 is a medium-light, vivid blue. In OKLCH its lightness is 66%, its chroma 0.152 and its hue 264°. Its hue sits on the cool side of the wheel. The nearest named color is Cornflower Blue (#6495ED), ΔE 0.018 away. Black text reads best on it, at 6.71:1.
| Hue family | Blues |
| Lightness | medium-light (66%) |
| Chroma | vivid (0.152) |
| Temperature | cool |
| Nearest name | Cornflower Blue (#6495ED) |
| Black text | 6.71:1 |
| White text | 3.12:1 |
Values
| HEX | #638FF0 |
| RGB | rgb(99, 143, 240) |
| HSL | hsl(221, 82%, 66%) |
| OKLCH | oklch(66.3% 0.152 264.3) |
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 #638FF0 | 3.12:1 | AA large text | Lc -63.5 | Content text, not long reading |
| Black text on #638FF0 | 6.71:1 | AA | Lc 46.0 | Large or bold text, headings |
| #638FF0 text on white | 3.12:1 | AA large text | Lc 58.1 | Large or bold text, headings |
| #638FF0 text on black | 6.71:1 | AA | Lc -43.7 | 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
#F2F6FC
oklch(97.2% 0.009 258.3)
-
Step 100
100
#E3EAF9
oklch(93.6% 0.022 265.8)
-
Step 200
200
#CBD9F5
oklch(88.4% 0.042 264.3)
-
Step 300
300
#A9C1F2
oklch(81% 0.074 264.4)
-
Step 400
400
#7B9FEB
oklch(70.7% 0.119 264.3)
-
Step 500
500 (this color)
#638FF0
oklch(66.3% 0.152 264.3)
-
Step 600
600
#406CD3
oklch(55.5% 0.166 264.3)
-
Step 700
700
#325AB7
oklch(49.1% 0.154 264)
-
Step 800
800
#2A4A94
oklch(42.7% 0.128 264.1)
-
Step 900
900
#263E76
oklch(37.6% 0.1 264.6)
-
Step 950
950
#162545
oklch(27% 0.063 263.8)
#638FF0 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) | #6599F4 | 0.026 |
| Deuteranopia (no green cones) | #528CEE | 0.020 |
| Tritanopia (no blue cones) | #00A5B4 | 0.133 |
| Achromatopsia (no color) | #929292 | 0.152 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #638FF0
#638FF0
oklch(66.3% 0.152 264.3)
- #BA8B00
#BA8B00
oklch(66.4% 0.136 84.5)
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 #638FF0, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cornflower Blue #6495ED ΔE 0.018
- Soft Blue #6488EA ΔE 0.019
- Chefchaouen Blue #4895EF ΔE 0.027
- Dark Sky Blue #448EE4 ΔE 0.036
- Dodger Blue #1E90FF ΔE 0.051
- Lavender Blue #8B88F8 ΔE 0.053
- Perrywinkle #8F8CE7 ΔE 0.055
- Cornflower #6A79F7 ΔE 0.058
Use #638FF0 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.