#637F95
Closest named color: Grey Blue (#647D8E). oklch(58.3% 0.047 242.2), rgb(99, 127, 149).
Aa
Black text reads best on this color (5.00:1).
About this color
#637F95 is a medium-dark, muted blue. In OKLCH its lightness is 58%, its chroma 0.047 and its hue 242°. Its hue sits on the cool side of the wheel. The nearest named color is Grey Blue (#647D8E), ΔE 0.011 away. Black text reads best on it, at 5.00:1.
| Hue family | Blues |
| Lightness | medium-dark (58%) |
| Chroma | muted (0.047) |
| Temperature | cool |
| Nearest name | Grey Blue (#647D8E) |
| Black text | 5.00:1 |
| White text | 4.19:1 |
Values
| HEX | #637F95 |
| RGB | rgb(99, 127, 149) |
| HSL | hsl(206, 20%, 49%) |
| OKLCH | oklch(58.3% 0.047 242.2) |
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 #637F95 | 4.19:1 | AA large text | Lc -74.4 | Content text, not long reading |
| Black text on #637F95 | 5.00:1 | AA | Lc 35.1 | Non-text elements, placeholder text |
| #637F95 text on white | 4.19:1 | AA large text | Lc 68.9 | Content text, not long reading |
| #637F95 text on black | 5.00:1 | AA | Lc -32.7 | 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 600.
-
Step 50
50
#F4F6F7
oklch(97.2% 0.003 228.8)
-
Step 100
100
#E6EAEE
oklch(93.5% 0.007 247.9)
-
Step 200
200
#D3DAE0
oklch(88.5% 0.011 243.7)
-
Step 300
300
#B5C3CD
oklch(80.9% 0.021 238.7)
-
Step 400
400
#8FA4B4
oklch(70.8% 0.033 240.9)
-
Step 500
500
#738DA2
oklch(63.1% 0.043 242.8)
-
Step 600
600 (this color)
#637F95
oklch(58.3% 0.047 242.2)
-
Step 700
700
#4B6478
oklch(49.1% 0.044 242.9)
-
Step 800
800
#3E5261
oklch(42.8% 0.035 241)
-
Step 900
900
#35444F
oklch(37.8% 0.027 240.2)
-
Step 950
950
#1F282F
oklch(27.1% 0.018 241.7)
#637F95 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) | #767F96 | 0.026 |
| Deuteranopia (no green cones) | #6F7995 | 0.022 |
| Tritanopia (no blue cones) | #538486 | 0.037 |
| Achromatopsia (no color) | #7C7C7C | 0.047 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #637F95
#637F95
oklch(58.3% 0.047 242.2)
- #90755F
#90755F
oklch(58.2% 0.047 60.9)
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 #637F95, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Grey Blue #647D8E ΔE 0.011
- Slate Gray #708090 ΔE 0.019
- Battleship Grey #6B7C85 ΔE 0.025
- Steel Grey #6F828A ΔE 0.026
- Steel #738595 ΔE 0.029
- Stormy Blue #507B9C ΔE 0.029
- Dusty Blue #5A86AD ΔE 0.037
- Off Blue #5684AE ΔE 0.038
Use #637F95 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.