#638BCD
Closest named color: Faded Blue (#658CBB). oklch(63.6% 0.109 260), rgb(99, 139, 205).
Aa
Black text reads best on this color (6.10:1).
About this color
#638BCD is a medium-light, moderately saturated blue. In OKLCH its lightness is 64%, its chroma 0.109 and its hue 260°. Its hue sits on the cool side of the wheel. The nearest named color is Faded Blue (#658CBB), ΔE 0.029 away. Black text reads best on it, at 6.10:1.
| Hue family | Blues |
| Lightness | medium-light (64%) |
| Chroma | moderately saturated (0.109) |
| Temperature | cool |
| Nearest name | Faded Blue (#658CBB) |
| Black text | 6.10:1 |
| White text | 3.43:1 |
Values
| HEX | #638BCD |
| RGB | rgb(99, 139, 205) |
| HSL | hsl(217, 51%, 60%) |
| OKLCH | oklch(63.6% 0.109 260) |
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 #638BCD | 3.43:1 | AA large text | Lc -67.3 | Content text, not long reading |
| Black text on #638BCD | 6.10:1 | AA | Lc 42.3 | Non-text elements, placeholder text |
| #638BCD text on white | 3.43:1 | AA large text | Lc 61.8 | Content text, not long reading |
| #638BCD text on black | 6.10:1 | AA | Lc -39.9 | 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
#F3F6FA
oklch(97.2% 0.006 255.5)
-
Step 100
100
#E4EAF5
oklch(93.6% 0.016 262.8)
-
Step 200
200
#CEDAED
oklch(88.5% 0.029 259.6)
-
Step 300
300
#ADC2E4
oklch(81% 0.053 260)
-
Step 400
400
#81A2D6
oklch(70.7% 0.085 259.3)
-
Step 500
500 (this color)
#638BCD
oklch(63.6% 0.109 260)
-
Step 600
600
#4872B8
oklch(55.5% 0.119 260.1)
-
Step 700
700
#3A609F
oklch(49.2% 0.11 260)
-
Step 800
800
#304E81
oklch(42.6% 0.092 260.4)
-
Step 900
900
#2B4167
oklch(37.6% 0.071 260.8)
-
Step 950
950
#19263C
oklch(26.8% 0.045 260.5)
#638BCD 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) | #7190D0 | 0.023 |
| Deuteranopia (no green cones) | #6586CC | 0.013 |
| Tritanopia (no blue cones) | #2E99A3 | 0.097 |
| Achromatopsia (no color) | #8A8A8A | 0.109 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #638BCD
#638BCD
oklch(63.6% 0.109 260)
- #AD8332
#AD8332
oklch(63.6% 0.11 80.6)
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 #638BCD, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Faded Blue #658CBB ΔE 0.029
- Dark Sky Blue #448EE4 ΔE 0.042
- Soft Blue #6488EA ΔE 0.047
- Cool Blue #4984B8 ΔE 0.047
- Cornflower Blue #6495ED ΔE 0.050
- Dusty Blue #5A86AD ΔE 0.051
- Off Blue #5684AE ΔE 0.052
- Chefchaouen Blue #4895EF ΔE 0.055
Use #638BCD 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.