#577AD5
Closest named color: Windows Blue (#3778BF). oklch(59.7% 0.144 266.3), rgb(87, 122, 213).
Aa
Black text reads best on this color (5.14:1).
About this color
#577AD5 is a medium-dark, vivid blue. In OKLCH its lightness is 60%, its chroma 0.144 and its hue 266°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.048 away. Black text reads best on it, at 5.14:1.
| Hue family | Blues |
| Lightness | medium-dark (60%) |
| Chroma | vivid (0.144) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 5.14:1 |
| White text | 4.07:1 |
Values
| HEX | #577AD5 |
| RGB | rgb(87, 122, 213) |
| HSL | hsl(223, 60%, 59%) |
| OKLCH | oklch(59.7% 0.144 266.3) |
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 #577AD5 | 4.07:1 | AA large text | Lc -73.3 | Content text, not long reading |
| Black text on #577AD5 | 5.14:1 | AA | Lc 36.3 | Non-text elements, placeholder text |
| #577AD5 text on white | 4.07:1 | AA large text | Lc 67.7 | Content text, not long reading |
| #577AD5 text on black | 5.14:1 | AA | Lc -33.9 | 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 500.
-
Step 50
50
#F2F5FC
oklch(97% 0.01 267.4)
-
Step 100
100
#E3EAF8
oklch(93.6% 0.02 264.5)
-
Step 200
200
#CDD9F4
oklch(88.5% 0.039 266.5)
-
Step 300
300
#ABC0EF
oklch(80.8% 0.071 266)
-
Step 400
400
#809EE7
oklch(70.6% 0.113 266.5)
-
Step 500
500 (this color)
#577AD5
oklch(59.7% 0.144 266.3)
-
Step 600
600
#486CCE
oklch(55.6% 0.157 266.2)
-
Step 700
700
#3A5AB3
oklch(49.2% 0.146 266.3)
-
Step 800
800
#304A90
oklch(42.7% 0.12 266.1)
-
Step 900
900
#2A3E73
oklch(37.6% 0.094 266.4)
-
Step 950
950
#192543
oklch(27% 0.058 266.1)
#577AD5 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) | #5184D8 | 0.026 |
| Deuteranopia (no green cones) | #4078D3 | 0.025 |
| Tritanopia (no blue cones) | #008E9D | 0.126 |
| Achromatopsia (no color) | #7E7E7E | 0.145 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #577AD5
#577AD5
oklch(59.7% 0.144 266.3)
- #9F7900
#9F7900
oklch(59.7% 0.122 86.5)
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 #577AD5, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.048
- Soft Blue #6488EA ΔE 0.049
- Dark Sky Blue #448EE4 ΔE 0.054
- Royal Blue #4169E1 ΔE 0.058
- Cornflower #6A79F7 ΔE 0.058
- Water Blue #0E87CC ΔE 0.058
- Cool Blue #4984B8 ΔE 0.059
- Steel Blue #4682B4 ΔE 0.063
Use #577AD5 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.