#577BB9
Closest named color: Steel Blue (#4682B4). oklch(58.3% 0.104 260.8), rgb(87, 123, 185).
Aa
Black text reads best on this color (4.93:1).
About this color
#577BB9 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 58%, its chroma 0.104 and its hue 261°. Its hue sits on the cool side of the wheel. The nearest named color is Steel Blue (#4682B4), ΔE 0.028 away. Black text reads best on it, at 4.93:1.
| Hue family | Blues |
| Lightness | medium-dark (58%) |
| Chroma | moderately saturated (0.104) |
| Temperature | cool |
| Nearest name | Steel Blue (#4682B4) |
| Black text | 4.93:1 |
| White text | 4.25:1 |
Values
| HEX | #577BB9 |
| RGB | rgb(87, 123, 185) |
| HSL | hsl(218, 41%, 53%) |
| OKLCH | oklch(58.3% 0.104 260.8) |
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 #577BB9 | 4.25:1 | AA large text | Lc -74.7 | Content text, not long reading |
| Black text on #577BB9 | 4.93:1 | AA | Lc 34.8 | Non-text elements, placeholder text |
| #577BB9 text on white | 4.25:1 | AA large text | Lc 69.3 | Content text, not long reading |
| #577BB9 text on black | 4.93:1 | AA | Lc -32.4 | 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
#F3F6FA
oklch(97.2% 0.006 255.5)
-
Step 100
100
#E5EAF3
oklch(93.6% 0.013 262.4)
-
Step 200
200
#CFDAEB
oklch(88.5% 0.026 259)
-
Step 300
300
#B0C2E0
oklch(81% 0.047 260.7)
-
Step 400
400
#86A1D0
oklch(70.6% 0.076 261.3)
-
Step 500
500
#688AC4
oklch(63.2% 0.096 260.7)
-
Step 600
600 (this color)
#577BB9
oklch(58.3% 0.104 260.8)
-
Step 700
700
#406097
oklch(49.1% 0.096 260.7)
-
Step 800
800
#354F7B
oklch(42.8% 0.08 260.4)
-
Step 900
900
#2E4263
oklch(37.8% 0.062 260.1)
-
Step 950
950
#1B273A
oklch(27.1% 0.039 259.4)
#577BB9 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) | #6380BC | 0.021 |
| Deuteranopia (no green cones) | #5777B8 | 0.011 |
| Tritanopia (no blue cones) | #248991 | 0.095 |
| Achromatopsia (no color) | #7B7B7B | 0.104 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #577BB9
#577BB9
oklch(58.3% 0.104 260.8)
- #9B7426
#9B7426
oklch(58.4% 0.105 80.9)
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 #577BB9, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Steel Blue #4682B4 ΔE 0.028
- Cool Blue #4984B8 ΔE 0.028
- Off Blue #5684AE ΔE 0.034
- Windows Blue #3778BF ΔE 0.035
- Dusty Blue #5A86AD ΔE 0.041
- Flat Blue #3C73A8 ΔE 0.046
- Stormy Blue #507B9C ΔE 0.047
- Dull Blue #49759C ΔE 0.050
Use #577BB9 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.