#577DC9
Closest named color: Cool Blue (#4984B8). oklch(59.7% 0.124 263), rgb(87, 125, 201).
Aa
Black text reads best on this color (5.18:1).
About this color
#577DC9 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 60%, its chroma 0.124 and its hue 263°. Its hue sits on the cool side of the wheel. The nearest named color is Cool Blue (#4984B8), ΔE 0.039 away. Black text reads best on it, at 5.18:1.
| Hue family | Blues |
| Lightness | medium-dark (60%) |
| Chroma | moderately saturated (0.124) |
| Temperature | cool |
| Nearest name | Cool Blue (#4984B8) |
| Black text | 5.18:1 |
| White text | 4.05:1 |
Values
| HEX | #577DC9 |
| RGB | rgb(87, 125, 201) |
| HSL | hsl(220, 51%, 56%) |
| OKLCH | oklch(59.7% 0.124 263) |
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 #577DC9 | 4.05:1 | AA large text | Lc -73.1 | Content text, not long reading |
| Black text on #577DC9 | 5.18:1 | AA | Lc 36.5 | Non-text elements, placeholder text |
| #577DC9 text on white | 4.05:1 | AA large text | Lc 67.6 | Content text, not long reading |
| #577DC9 text on black | 5.18:1 | AA | Lc -34.1 | 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
#F3F6FB
oklch(97.2% 0.007 260.7)
-
Step 100
100
#E4EAF6
oklch(93.6% 0.017 264.5)
-
Step 200
200
#CEDAF0
oklch(88.6% 0.033 262.7)
-
Step 300
300
#ACC1E9
oklch(80.9% 0.061 263.2)
-
Step 400
400
#80A0DE
oklch(70.6% 0.098 263.1)
-
Step 500
500 (this color)
#577DC9
oklch(59.7% 0.124 263)
-
Step 600
600
#4870C2
oklch(55.6% 0.135 263.1)
-
Step 700
700
#395DA7
oklch(49% 0.126 263)
-
Step 800
800
#304D87
oklch(42.8% 0.103 262.8)
-
Step 900
900
#2A406C
oklch(37.6% 0.081 263)
-
Step 950
950
#19263F
oklch(27% 0.05 262.6)
#577DC9 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) | #5E84CC | 0.022 |
| Deuteranopia (no green cones) | #4F79C7 | 0.015 |
| Tritanopia (no blue cones) | #008E99 | 0.112 |
| Achromatopsia (no color) | #7E7E7E | 0.124 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #577DC9
#577DC9
oklch(59.7% 0.124 263)
- #A27700
#A27700
oklch(59.6% 0.123 83.2)
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 #577DC9, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cool Blue #4984B8 ΔE 0.039
- Windows Blue #3778BF ΔE 0.039
- Steel Blue #4682B4 ΔE 0.043
- Water Blue #0E87CC ΔE 0.049
- Off Blue #5684AE ΔE 0.051
- Dark Sky Blue #448EE4 ΔE 0.055
- Faded Blue #658CBB ΔE 0.055
- Dusty Blue #5A86AD ΔE 0.056
Use #577DC9 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.