#638BBF
Closest named color: Faded Blue (#658CBB). oklch(62.9% 0.091 255.3), rgb(99, 139, 191).
Aa
Black text reads best on this color (5.97:1).
About this color
#638BBF is a medium-light, moderately saturated blue. In OKLCH its lightness is 63%, its chroma 0.091 and its hue 255°. Its hue sits on the cool side of the wheel. The nearest named color is Faded Blue (#658CBB), ΔE 0.008 away. Black text reads best on it, at 5.97:1.
| Hue family | Blues |
| Lightness | medium-light (63%) |
| Chroma | moderately saturated (0.091) |
| Temperature | cool |
| Nearest name | Faded Blue (#658CBB) |
| Black text | 5.97:1 |
| White text | 3.51:1 |
Values
| HEX | #638BBF |
| RGB | rgb(99, 139, 191) |
| HSL | hsl(214, 42%, 57%) |
| OKLCH | oklch(62.9% 0.091 255.3) |
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 #638BBF | 3.51:1 | AA large text | Lc -68.1 | Content text, not long reading |
| Black text on #638BBF | 5.97:1 | AA | Lc 41.5 | Non-text elements, placeholder text |
| #638BBF text on white | 3.51:1 | AA large text | Lc 62.6 | Content text, not long reading |
| #638BBF text on black | 5.97:1 | AA | Lc -39.1 | 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
#F3F6F9
oklch(97.2% 0.005 247.9)
-
Step 100
100
#E4EAF3
oklch(93.5% 0.014 258.3)
-
Step 200
200
#CFDAEA
oklch(88.5% 0.025 257.6)
-
Step 300
300
#AEC3DE
oklch(81% 0.045 254.8)
-
Step 400
400
#83A3CD
oklch(70.7% 0.071 255.4)
-
Step 500
500 (this color)
#638BBF
oklch(62.9% 0.091 255.3)
-
Step 600
600
#4A75AC
oklch(55.6% 0.099 255.2)
-
Step 700
700
#3B6294
oklch(49.1% 0.092 255.3)
-
Step 800
800
#315078
oklch(42.6% 0.076 255.4)
-
Step 900
900
#2C4361
oklch(37.8% 0.059 255.5)
-
Step 950
950
#1A2739
oklch(27% 0.038 256.7)
#638BBF 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) | #778EC1 | 0.027 |
| Deuteranopia (no green cones) | #6C85BE | 0.018 |
| Tritanopia (no blue cones) | #3B979D | 0.081 |
| Achromatopsia (no color) | #898989 | 0.091 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #638BBF
#638BBF
oklch(62.9% 0.091 255.3)
- #A98146
#A98146
oklch(63% 0.091 75.5)
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 #638BBF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Faded Blue #658CBB ΔE 0.008
- Dusty Blue #5A86AD ΔE 0.031
- Off Blue #5684AE ΔE 0.035
- Cool Blue #4984B8 ΔE 0.037
- Silver Lake Blue #778DA9 ΔE 0.042
- Steel Blue #4682B4 ΔE 0.045
- Blue Grey #758DA3 ΔE 0.049
- Light Slate Gray #778899 ΔE 0.059
Use #638BBF 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.