#638CFB
Closest named color: Soft Blue (#6488EA). oklch(66.4% 0.171 266.5), rgb(99, 140, 251).
Aa
Black text reads best on this color (6.67:1).
About this color
#638CFB is a medium-light, vivid blue. In OKLCH its lightness is 66%, its chroma 0.171 and its hue 267°. Its hue sits on the cool side of the wheel. The nearest named color is Soft Blue (#6488EA), ΔE 0.026 away. Black text reads best on it, at 6.67:1.
| Hue family | Blues |
| Lightness | medium-light (66%) |
| Chroma | vivid (0.171) |
| Temperature | cool |
| Nearest name | Soft Blue (#6488EA) |
| Black text | 6.67:1 |
| White text | 3.14:1 |
Values
| HEX | #638CFB |
| RGB | rgb(99, 140, 251) |
| HSL | hsl(224, 95%, 69%) |
| OKLCH | oklch(66.4% 0.171 266.5) |
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 #638CFB | 3.14:1 | AA large text | Lc -63.7 | Content text, not long reading |
| Black text on #638CFB | 6.67:1 | AA | Lc 45.8 | Large or bold text, headings |
| #638CFB text on white | 3.14:1 | AA large text | Lc 58.3 | Large or bold text, headings |
| #638CFB text on black | 6.67:1 | AA | Lc -43.5 | 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
#F2F5FD
oklch(97% 0.011 269.6)
-
Step 100
100
#E2EAFB
oklch(93.6% 0.025 265.6)
-
Step 200
200
#CBD9F9
oklch(88.5% 0.047 266.7)
-
Step 300
300
#A8C0F8
oklch(81% 0.084 266.5)
-
Step 400
400
#7A9DF4
oklch(70.7% 0.134 266.4)
-
Step 500
500 (this color)
#638CFB
oklch(66.4% 0.171 266.5)
-
Step 600
600
#4168DE
oklch(55.6% 0.185 266.5)
-
Step 700
700
#3456C1
oklch(49.2% 0.172 266.6)
-
Step 800
800
#2B479C
oklch(42.7% 0.143 266.6)
-
Step 900
900
#263C7C
oklch(37.6% 0.112 266.7)
-
Step 950
950
#162449
oklch(27% 0.071 266.2)
#638CFB 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) | #5898FF | 0.030 |
| Deuteranopia (no green cones) | #408BF9 | 0.033 |
| Tritanopia (no blue cones) | #00A5B7 | 0.147 |
| Achromatopsia (no color) | #919191 | 0.171 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #638CFB
#638CFB
oklch(66.4% 0.171 266.5)
- #B88C00
#B88C00
oklch(66.4% 0.136 86.2)
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 #638CFB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Soft Blue #6488EA ΔE 0.026
- Cornflower Blue #6495ED ΔE 0.034
- Chefchaouen Blue #4895EF ΔE 0.039
- Cornflower #6A79F7 ΔE 0.046
- Dark Sky Blue #448EE4 ΔE 0.047
- Dodger Blue #1E90FF ΔE 0.048
- Lavender Blue #8B88F8 ΔE 0.049
- Periwinkle #8E82FE ΔE 0.057
Use #638CFB 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.