#638BC4
Closest named color: Faded Blue (#658CBB). oklch(63.1% 0.097 257.3), rgb(99, 139, 196).
Aa
Black text reads best on this color (6.02:1).
About this color
#638BC4 is a medium-light, moderately saturated blue. In OKLCH its lightness is 63%, its chroma 0.097 and its hue 257°. Its hue sits on the cool side of the wheel. The nearest named color is Faded Blue (#658CBB), ΔE 0.015 away. Black text reads best on it, at 6.02:1.
| Hue family | Blues |
| Lightness | medium-light (63%) |
| Chroma | moderately saturated (0.097) |
| Temperature | cool |
| Nearest name | Faded Blue (#658CBB) |
| Black text | 6.02:1 |
| White text | 3.48:1 |
Values
| HEX | #638BC4 |
| RGB | rgb(99, 139, 196) |
| HSL | hsl(215, 45%, 58%) |
| OKLCH | oklch(63.1% 0.097 257.3) |
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 #638BC4 | 3.48:1 | AA large text | Lc -67.8 | Content text, not long reading |
| Black text on #638BC4 | 6.02:1 | AA | Lc 41.7 | Non-text elements, placeholder text |
| #638BC4 text on white | 3.48:1 | AA large text | Lc 62.3 | Content text, not long reading |
| #638BC4 text on black | 6.02:1 | AA | Lc -39.4 | 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
#F3F6FA
oklch(97.2% 0.006 255.5)
-
Step 100
100
#E4EAF3
oklch(93.5% 0.014 258.3)
-
Step 200
200
#CEDAEB
oklch(88.4% 0.027 257)
-
Step 300
300
#AEC2E0
oklch(80.9% 0.048 258.4)
-
Step 400
400
#82A3D0
oklch(70.8% 0.076 256.3)
-
Step 500
500 (this color)
#638BC4
oklch(63.1% 0.097 257.3)
-
Step 600
600
#4A74B0
oklch(55.6% 0.105 257.4)
-
Step 700
700
#3B6198
oklch(49.1% 0.099 257.6)
-
Step 800
800
#31507B
oklch(42.8% 0.081 256.8)
-
Step 900
900
#2B4263
oklch(37.6% 0.064 257.4)
-
Step 950
950
#1A273A
oklch(27% 0.04 257.8)
#638BC4 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) | #758EC6 | 0.024 |
| Deuteranopia (no green cones) | #6985C3 | 0.017 |
| Tritanopia (no blue cones) | #37989F | 0.087 |
| Achromatopsia (no color) | #898989 | 0.097 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #638BC4
#638BC4
oklch(63.1% 0.097 257.3)
- #AA8140
#AA8140
oklch(63% 0.097 76.9)
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 #638BC4, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Faded Blue #658CBB ΔE 0.015
- Dusty Blue #5A86AD ΔE 0.038
- Cool Blue #4984B8 ΔE 0.040
- Off Blue #5684AE ΔE 0.040
- Steel Blue #4682B4 ΔE 0.047
- Silver Lake Blue #778DA9 ΔE 0.048
- Dark Sky Blue #448EE4 ΔE 0.053
- Blue Grey #758DA3 ΔE 0.056
Use #638BC4 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.