#638D9B
Closest named color: Blue Grey (#758DA3). oklch(61.8% 0.051 220.6), rgb(99, 141, 155).
Aa
Black text reads best on this color (5.81:1).
About this color
#638D9B is a medium-dark, muted teal or cyan. In OKLCH its lightness is 62%, its chroma 0.051 and its hue 221°. Its hue sits on the cool side of the wheel. The nearest named color is Blue Grey (#758DA3), ΔE 0.026 away. Black text reads best on it, at 5.81:1.
| Hue family | Teals and cyans |
| Lightness | medium-dark (62%) |
| Chroma | muted (0.051) |
| Temperature | cool |
| Nearest name | Blue Grey (#758DA3) |
| Black text | 5.81:1 |
| White text | 3.61:1 |
Values
| HEX | #638D9B |
| RGB | rgb(99, 141, 155) |
| HSL | hsl(195, 22%, 50%) |
| OKLCH | oklch(61.8% 0.051 220.6) |
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 #638D9B | 3.61:1 | AA large text | Lc -69.2 | Content text, not long reading |
| Black text on #638D9B | 5.81:1 | AA | Lc 40.4 | Non-text elements, placeholder text |
| #638D9B text on white | 3.61:1 | AA large text | Lc 63.7 | Content text, not long reading |
| #638D9B text on black | 5.81:1 | AA | Lc -38.0 | 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
#F3F6F7
oklch(97.1% 0.003 219.5)
-
Step 100
100
#E5EBED
oklch(93.6% 0.007 219.6)
-
Step 200
200
#D0DBDF
oklch(88.4% 0.013 221.4)
-
Step 300
300
#B0C5CC
oklch(81% 0.025 219.8)
-
Step 400
400
#86A7B2
oklch(70.7% 0.04 220.1)
-
Step 500
500 (this color)
#638D9B
oklch(61.8% 0.051 220.6)
-
Step 600
600
#4D7B8A
oklch(55.6% 0.055 220.6)
-
Step 700
700
#3E6875
oklch(49.2% 0.051 219.7)
-
Step 800
800
#34555F
oklch(42.8% 0.042 219.1)
-
Step 900
900
#2D464E
oklch(37.7% 0.034 219.9)
-
Step 950
950
#1B292E
oklch(27% 0.021 222)
#638D9B 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) | #848B9C | 0.042 |
| Deuteranopia (no green cones) | #7C849B | 0.039 |
| Tritanopia (no blue cones) | #4F9291 | 0.032 |
| Achromatopsia (no color) | #878787 | 0.051 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #638D9B
#638D9B
oklch(61.8% 0.051 220.6)
- #A17C6E
#A17C6E
oklch(61.8% 0.051 41.7)
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 #638D9B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Blue Grey #758DA3 ΔE 0.026
- Light Slate Gray #778899 ΔE 0.027
- Steel #738595 ΔE 0.027
- Silver Lake Blue #778DA9 ΔE 0.035
- Steel Grey #6F828A ΔE 0.035
- Slate Gray #708090 ΔE 0.037
- Dusty Blue #5A86AD ΔE 0.041
- Grey Blue #647D8E ΔE 0.045
Use #638D9B 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.