#657B99
Closest named color: Grey Blue (#647D8E). oklch(57.7% 0.053 256.2), rgb(101, 123, 153).
Aa
Black text reads best on this color (4.84:1).
About this color
#657B99 is a medium-dark, muted blue. In OKLCH its lightness is 58%, its chroma 0.053 and its hue 256°. Its hue sits on the cool side of the wheel. The nearest named color is Grey Blue (#647D8E), ΔE 0.020 away. Black text reads best on it, at 4.84:1.
| Hue family | Blues |
| Lightness | medium-dark (58%) |
| Chroma | muted (0.053) |
| Temperature | cool |
| Nearest name | Grey Blue (#647D8E) |
| Black text | 4.84:1 |
| White text | 4.33:1 |
Values
| HEX | #657B99 |
| RGB | rgb(101, 123, 153) |
| HSL | hsl(215, 20%, 50%) |
| OKLCH | oklch(57.7% 0.053 256.2) |
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 #657B99 | 4.33:1 | AA large text | Lc -75.5 | Fine for body text |
| Black text on #657B99 | 4.84:1 | AA | Lc 34.1 | Non-text elements, placeholder text |
| #657B99 text on white | 4.33:1 | AA large text | Lc 70.0 | Content text, not long reading |
| #657B99 text on black | 4.84:1 | AA | Lc -31.7 | 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
#F4F5F8
oklch(97% 0.004 271.4)
-
Step 100
100
#E7EAEE
oklch(93.6% 0.006 255.5)
-
Step 200
200
#D4DAE2
oklch(88.6% 0.013 255.5)
-
Step 300
300
#B7C2D0
oklch(81% 0.023 254.4)
-
Step 400
400
#91A2B9
oklch(70.7% 0.039 256)
-
Step 500
500
#768BA7
oklch(63% 0.049 255.7)
-
Step 600
600 (this color)
#657B99
oklch(57.7% 0.053 256.2)
-
Step 700
700
#4E627D
oklch(49.1% 0.05 256)
-
Step 800
800
#405066
oklch(42.7% 0.042 256.4)
-
Step 900
900
#374253
oklch(37.6% 0.033 259)
-
Step 950
950
#202730
oklch(27% 0.02 254.8)
#657B99 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) | #707C9A | 0.016 |
| Deuteranopia (no green cones) | #6B7798 | 0.013 |
| Tritanopia (no blue cones) | #558185 | 0.046 |
| Achromatopsia (no color) | #797979 | 0.053 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #657B99
#657B99
oklch(57.7% 0.053 256.2)
- #8C7556
#8C7556
oklch(57.6% 0.053 74.7)
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 #657B99, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Grey Blue #647D8E ΔE 0.020
- Stormy Blue #507B9C ΔE 0.025
- Slate Gray #708090 ΔE 0.028
- Battleship Grey #6B7C85 ΔE 0.033
- Cerulean #457B9D ΔE 0.036
- Off Blue #5684AE ΔE 0.037
- Dusty Blue #5A86AD ΔE 0.038
- Lavender Gray #7E7F9A ΔE 0.038
Use #657B99 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.