#638FFB
Closest named color: Soft Blue (#6488EA). oklch(67% 0.167 265.5), rgb(99, 143, 251).
Aa
Black text reads best on this color (6.85:1).
About this color
#638FFB is a medium-light, vivid blue. In OKLCH its lightness is 67%, its chroma 0.167 and its hue 265°. Its hue sits on the cool side of the wheel. The nearest named color is Soft Blue (#6488EA), ΔE 0.029 away. Black text reads best on it, at 6.85:1.
| Hue family | Blues |
| Lightness | medium-light (67%) |
| Chroma | vivid (0.167) |
| Temperature | cool |
| Nearest name | Soft Blue (#6488EA) |
| Black text | 6.85:1 |
| White text | 3.06:1 |
Values
| HEX | #638FFB |
| RGB | rgb(99, 143, 251) |
| HSL | hsl(223, 95%, 69%) |
| OKLCH | oklch(67% 0.167 265.5) |
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 #638FFB | 3.06:1 | AA large text | Lc -62.6 | Content text, not long reading |
| Black text on #638FFB | 6.85:1 | AA | Lc 46.8 | Large or bold text, headings |
| #638FFB text on white | 3.06:1 | AA large text | Lc 57.3 | Large or bold text, headings |
| #638FFB text on black | 6.85:1 | AA | Lc -44.5 | 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 400.
-
Step 50
50
#F1F6FF
oklch(97.2% 0.013 262.4)
-
Step 100
100
#E0EAFF
oklch(93.6% 0.03 265.3)
-
Step 200
200
#C8D9FF
oklch(88.5% 0.056 266.2)
-
Step 300
300
#A3C0FF
oklch(80.9% 0.095 265.2)
-
Step 400
400 (this color)
#638FFB
oklch(67% 0.167 265.5)
-
Step 500
500
#4F7FFF
oklch(63.1% 0.197 265.6)
-
Step 600
600
#3061F8
oklch(55.7% 0.231 265.4)
-
Step 700
700
#244ED8
oklch(49% 0.216 265.5)
-
Step 800
800
#1E41AF
oklch(42.6% 0.18 265.4)
-
Step 900
900
#1D398A
oklch(37.7% 0.139 265.5)
-
Step 950
950
#112251
oklch(26.9% 0.089 265.7)
#638FFB 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) | #5D9BFF | 0.030 |
| Deuteranopia (no green cones) | #478DF9 | 0.028 |
| Tritanopia (no blue cones) | #00A7B9 | 0.143 |
| Achromatopsia (no color) | #939393 | 0.167 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #638FFB
#638FFB
oklch(67% 0.167 265.5)
- #BB8D00
#BB8D00
oklch(66.9% 0.137 85.3)
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 #638FFB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Soft Blue #6488EA ΔE 0.029
- Cornflower Blue #6495ED ΔE 0.029
- Chefchaouen Blue #4895EF ΔE 0.035
- Dark Sky Blue #448EE4 ΔE 0.047
- Dodger Blue #1E90FF ΔE 0.048
- Lavender Blue #8B88F8 ΔE 0.050
- Cornflower #6A79F7 ΔE 0.054
- Periwinkle #8E82FE ΔE 0.060
Use #638FFB 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.