#577B9C
Closest named color: Stormy Blue (#507B9C). oklch(56.9% 0.066 246.9), rgb(87, 123, 156).
Aa
Black text reads best on this color (4.71:1).
About this color
#577B9C is a medium-dark, muted blue. In OKLCH its lightness is 57%, its chroma 0.066 and its hue 247°. Its hue sits on the cool side of the wheel. The nearest named color is Stormy Blue (#507B9C), ΔE 0.008 away. Black text reads best on it, at 4.71:1.
| Hue family | Blues |
| Lightness | medium-dark (57%) |
| Chroma | muted (0.066) |
| Temperature | cool |
| Nearest name | Stormy Blue (#507B9C) |
| Black text | 4.71:1 |
| White text | 4.45:1 |
Values
| HEX | #577B9C |
| RGB | rgb(87, 123, 156) |
| HSL | hsl(209, 28%, 48%) |
| OKLCH | oklch(56.9% 0.066 246.9) |
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 #577B9C | 4.45:1 | AA large text | Lc -76.3 | Fine for body text |
| Black text on #577B9C | 4.71:1 | AA | Lc 33.3 | Non-text elements, placeholder text |
| #577B9C text on white | 4.45:1 | AA large text | Lc 70.8 | Content text, not long reading |
| #577B9C text on black | 4.71:1 | AA | Lc -30.8 | 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
#F3F6F8
oklch(97.1% 0.004 236.5)
-
Step 100
100
#E5EAEF
oklch(93.5% 0.009 247.9)
-
Step 200
200
#D1DAE4
oklch(88.4% 0.017 250.9)
-
Step 300
300
#B2C3D3
oklch(80.9% 0.029 246.5)
-
Step 400
400
#89A4BD
oklch(70.7% 0.047 246.5)
-
Step 500
500
#6C8DAC
oklch(63% 0.06 247.2)
-
Step 600
600 (this color)
#577B9C
oklch(56.9% 0.066 246.9)
-
Step 700
700
#446482
oklch(49.1% 0.061 247.6)
-
Step 800
800
#385269
oklch(42.8% 0.05 246)
-
Step 900
900
#304456
oklch(37.8% 0.04 246.3)
-
Step 950
950
#1D2832
oklch(27.1% 0.024 246.3)
#577B9C 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) | #6E7B9E | 0.030 |
| Deuteranopia (no green cones) | #65749B | 0.025 |
| Tritanopia (no blue cones) | #3C8386 | 0.056 |
| Achromatopsia (no color) | #777777 | 0.066 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #577B9C
#577B9C
oklch(56.9% 0.066 246.9)
- #92704D
#92704D
oklch(57% 0.066 66.7)
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 #577B9C, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Stormy Blue #507B9C ΔE 0.008
- Cerulean #457B9D ΔE 0.019
- Dull Blue #49759C ΔE 0.025
- Grey Blue #647D8E ΔE 0.028
- Metallic Blue #4F738E ΔE 0.031
- Off Blue #5684AE ΔE 0.033
- Dusty Blue #5A86AD ΔE 0.037
- Steel Blue #4682B4 ΔE 0.039
Use #577B9C 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.