#646F81
Closest named color: Battleship Gray (#6C757D). oklch(53.9% 0.031 260.3), rgb(100, 111, 129).
Aa
White text reads best on this color (5.08:1).
About this color
#646F81 is a medium-dark, muted blue. In OKLCH its lightness is 54%, its chroma 0.031 and its hue 260°. Its hue sits on the cool side of the wheel. The nearest named color is Battleship Gray (#6C757D), ΔE 0.024 away. White text reads best on it, at 5.08:1.
| Hue family | Blues |
| Lightness | medium-dark (54%) |
| Chroma | muted (0.031) |
| Temperature | cool |
| Nearest name | Battleship Gray (#6C757D) |
| Black text | 4.13:1 |
| White text | 5.08:1 |
Values
| HEX | #646F81 |
| RGB | rgb(100, 111, 129) |
| HSL | hsl(217, 13%, 45%) |
| OKLCH | oklch(53.9% 0.031 260.3) |
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 #646F81 | 5.08:1 | AA | Lc -80.5 | Fine for body text |
| Black text on #646F81 | 4.13:1 | AA large text | Lc 29.0 | Dividers and decoration only |
| #646F81 text on white | 5.08:1 | AA | Lc 75.1 | Fine for body text |
| #646F81 text on black | 4.13:1 | AA large text | Lc -26.6 | Dividers and decoration only |
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
#F5F5F7
oklch(97.1% 0.003 286.4)
-
Step 100
100
#E8EAED
oklch(93.6% 0.005 258.3)
-
Step 200
200
#D6D9DE
oklch(88.4% 0.008 260.7)
-
Step 300
300
#BBC1CA
oklch(80.9% 0.014 258.4)
-
Step 400
400
#99A1AF
oklch(70.7% 0.022 261.7)
-
Step 500
500
#808A9B
oklch(63.1% 0.028 261.1)
-
Step 600
600 (this color)
#646F81
oklch(53.9% 0.031 260.3)
-
Step 700
700
#576172
oklch(49% 0.03 261.1)
-
Step 800
800
#474F5C
oklch(42.5% 0.024 260.1)
-
Step 900
900
#3C424C
oklch(37.7% 0.019 260.7)
-
Step 950
950
#23272C
oklch(27.1% 0.011 254)
#646F81 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) | #697082 | 0.008 |
| Deuteranopia (no green cones) | #666D81 | 0.006 |
| Tritanopia (no blue cones) | #5D7375 | 0.028 |
| Achromatopsia (no color) | #6E6E6E | 0.031 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #646F81
#646F81
oklch(53.9% 0.031 260.3)
- #786D5A
#786D5A
oklch(54% 0.032 81.3)
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 #646F81, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Battleship Gray #6C757D ΔE 0.024
- Metallic Blue #4F738E ΔE 0.031
- Dim Gray #696969 ΔE 0.036
- Battleship Grey #6B7C85 ΔE 0.040
- Grey Blue #647D8E ΔE 0.040
- Slate #516572 ΔE 0.046
- Stormy Blue #507B9C ΔE 0.049
- Dull Blue #49759C ΔE 0.049
Use #646F81 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.