#637E92
Closest named color: Grey Blue (#647D8E). oklch(57.9% 0.044 240.6), rgb(99, 126, 146).
Aa
Black text reads best on this color (4.92:1).
About this color
#637E92 is a medium-dark, muted blue. In OKLCH its lightness is 58%, its chroma 0.044 and its hue 241°. Its hue sits on the cool side of the wheel. The nearest named color is Grey Blue (#647D8E), ΔE 0.006 away. Black text reads best on it, at 4.92:1.
| Hue family | Blues |
| Lightness | medium-dark (58%) |
| Chroma | muted (0.044) |
| Temperature | cool |
| Nearest name | Grey Blue (#647D8E) |
| Black text | 4.92:1 |
| White text | 4.25:1 |
Values
| HEX | #637E92 |
| RGB | rgb(99, 126, 146) |
| HSL | hsl(206, 19%, 48%) |
| OKLCH | oklch(57.9% 0.044 240.6) |
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 #637E92 | 4.25:1 | AA large text | Lc -74.9 | Content text, not long reading |
| Black text on #637E92 | 4.92:1 | AA | Lc 34.7 | Non-text elements, placeholder text |
| #637E92 text on white | 4.25:1 | AA large text | Lc 69.4 | Content text, not long reading |
| #637E92 text on black | 4.92:1 | AA | Lc -32.2 | 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
#E7EAED
oklch(93.6% 0.005 247.9)
-
Step 200
200
#D3DAE0
oklch(88.5% 0.011 243.7)
-
Step 300
300
#B6C3CC
oklch(81% 0.019 237.8)
-
Step 400
400
#90A4B3
oklch(70.8% 0.031 240.4)
-
Step 500
500
#748DA0
oklch(63.1% 0.04 241.1)
-
Step 600
600 (this color)
#637E92
oklch(57.9% 0.044 240.6)
-
Step 700
700
#4C6476
oklch(49.1% 0.041 241)
-
Step 800
800
#3E5260
oklch(42.8% 0.034 239.1)
-
Step 900
900
#35444E
oklch(37.8% 0.026 237.6)
-
Step 950
950
#1F282E
oklch(27.1% 0.017 237.4)
#637E92 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) | #767D93 | 0.026 |
| Deuteranopia (no green cones) | #6F7892 | 0.022 |
| Tritanopia (no blue cones) | #548384 | 0.036 |
| Achromatopsia (no color) | #7B7B7B | 0.044 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #637E92
#637E92
oklch(57.9% 0.044 240.6)
- #8E7560
#8E7560
oklch(58.1% 0.044 61.8)
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 #637E92, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Grey Blue #647D8E ΔE 0.006
- Slate Gray #708090 ΔE 0.019
- Battleship Grey #6B7C85 ΔE 0.021
- Steel Grey #6F828A ΔE 0.025
- Stormy Blue #507B9C ΔE 0.030
- Steel #738595 ΔE 0.031
- Battleship Gray #6C757D ΔE 0.035
- Cerulean #457B9D ΔE 0.040
Use #637E92 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.