#638DAB
Closest named color: Blue Grey (#758DA3). oklch(62.4% 0.065 240.2), rgb(99, 141, 171).
Aa
Black text reads best on this color (5.92:1).
About this color
#638DAB is a medium-light, muted blue. In OKLCH its lightness is 62%, its chroma 0.065 and its hue 240°. Its hue sits on the cool side of the wheel. The nearest named color is Blue Grey (#758DA3), ΔE 0.024 away. Black text reads best on it, at 5.92:1.
| Hue family | Blues |
| Lightness | medium-light (62%) |
| Chroma | muted (0.065) |
| Temperature | cool |
| Nearest name | Blue Grey (#758DA3) |
| Black text | 5.92:1 |
| White text | 3.54:1 |
Values
| HEX | #638DAB |
| RGB | rgb(99, 141, 171) |
| HSL | hsl(205, 30%, 53%) |
| OKLCH | oklch(62.4% 0.065 240.2) |
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 #638DAB | 3.54:1 | AA large text | Lc -68.4 | Content text, not long reading |
| Black text on #638DAB | 5.92:1 | AA | Lc 41.1 | Non-text elements, placeholder text |
| #638DAB text on white | 3.54:1 | AA large text | Lc 62.9 | Content text, not long reading |
| #638DAB text on black | 5.92:1 | AA | Lc -38.7 | 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
#F3F6F8
oklch(97.1% 0.004 236.5)
-
Step 100
100
#E5EBEF
oklch(93.7% 0.008 236.6)
-
Step 200
200
#CFDBE4
oklch(88.5% 0.018 240)
-
Step 300
300
#AFC4D3
oklch(80.9% 0.031 238.9)
-
Step 400
400
#84A5BE
oklch(70.6% 0.052 241.1)
-
Step 500
500 (this color)
#638DAB
oklch(62.4% 0.065 240.2)
-
Step 600
600
#4B7999
oklch(55.6% 0.071 240.1)
-
Step 700
700
#3C6682
oklch(49.2% 0.065 239.2)
-
Step 800
800
#32536A
oklch(42.7% 0.054 240.2)
-
Step 900
900
#2C4556
oklch(37.8% 0.042 239.1)
-
Step 950
950
#1A2832
oklch(26.9% 0.027 240.1)
#638DAB 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) | #808CAC | 0.036 |
| Deuteranopia (no green cones) | #7685AA | 0.030 |
| Tritanopia (no blue cones) | #479497 | 0.051 |
| Achromatopsia (no color) | #888888 | 0.065 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #638DAB
#638DAB
oklch(62.4% 0.065 240.2)
- #A57E5F
#A57E5F
oklch(62.3% 0.065 59.7)
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 #638DAB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Blue Grey #758DA3 ΔE 0.024
- Silver Lake Blue #778DA9 ΔE 0.024
- Dusty Blue #5A86AD ΔE 0.025
- Faded Blue #658CBB ΔE 0.026
- Off Blue #5684AE ΔE 0.033
- Light Slate Gray #778899 ΔE 0.033
- Steel #738595 ΔE 0.037
- Slate Gray #708090 ΔE 0.047
Use #638DAB 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.