#637987
Closest named color: Grey Blue (#647D8E). oklch(56.4% 0.034 236.1), rgb(99, 121, 135).
Aa
Black text reads best on this color (4.61:1).
About this color
#637987 is a medium-dark, muted blue. In OKLCH its lightness is 56%, its chroma 0.034 and its hue 236°. Its hue sits on the cool side of the wheel. The nearest named color is Grey Blue (#647D8E), ΔE 0.014 away. Black text reads best on it, at 4.61:1.
| Hue family | Blues |
| Lightness | medium-dark (56%) |
| Chroma | muted (0.034) |
| Temperature | cool |
| Nearest name | Grey Blue (#647D8E) |
| Black text | 4.61:1 |
| White text | 4.55:1 |
Values
| HEX | #637987 |
| RGB | rgb(99, 121, 135) |
| HSL | hsl(203, 15%, 46%) |
| OKLCH | oklch(56.4% 0.034 236.1) |
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 #637987 | 4.55:1 | AA | Lc -77.1 | Fine for body text |
| Black text on #637987 | 4.61:1 | AA | Lc 32.5 | Non-text elements, placeholder text |
| #637987 text on white | 4.55:1 | AA | Lc 71.6 | Content text, not long reading |
| #637987 text on black | 4.61:1 | AA | Lc -30.1 | 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 600.
-
Step 50
50
#F4F6F7
oklch(97.2% 0.003 228.8)
-
Step 100
100
#E7EAEC
oklch(93.5% 0.004 236.5)
-
Step 200
200
#D4DADE
oklch(88.5% 0.009 236.6)
-
Step 300
300
#B8C2C9
oklch(80.8% 0.015 238.1)
-
Step 400
400
#93A3AE
oklch(70.6% 0.024 237.8)
-
Step 500
500
#788D9A
oklch(63.1% 0.031 235.2)
-
Step 600
600 (this color)
#637987
oklch(56.4% 0.034 236.1)
-
Step 700
700
#506470
oklch(49.1% 0.031 234.6)
-
Step 800
800
#42515C
oklch(42.6% 0.026 240)
-
Step 900
900
#38434B
oklch(37.6% 0.02 239.7)
-
Step 950
950
#21282C
oklch(27.2% 0.012 232.9)
#637987 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) | #737888 | 0.022 |
| Deuteranopia (no green cones) | #6E7487 | 0.020 |
| Tritanopia (no blue cones) | #587D7D | 0.027 |
| Achromatopsia (no color) | #767676 | 0.034 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #637987
#637987
oklch(56.4% 0.034 236.1)
- #867163
#867163
oklch(56.5% 0.034 55.6)
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 #637987, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Grey Blue #647D8E ΔE 0.014
- Battleship Grey #6B7C85 ΔE 0.015
- Battleship Gray #6C757D ΔE 0.019
- Slate Gray #708090 ΔE 0.030
- Steel Grey #6F828A ΔE 0.032
- Metallic Blue #4F738E ΔE 0.035
- Stormy Blue #507B9C ΔE 0.037
- Cerulean #457B9D ΔE 0.045
Use #637987 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.