#577BC0
Closest named color: Cool Blue (#4984B8). oklch(58.7% 0.114 262.5), rgb(87, 123, 192).
Aa
Black text reads best on this color (4.99:1).
About this color
#577BC0 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 59%, its chroma 0.114 and its hue 262°. Its hue sits on the cool side of the wheel. The nearest named color is Cool Blue (#4984B8), ΔE 0.033 away. Black text reads best on it, at 4.99:1.
| Hue family | Blues |
| Lightness | medium-dark (59%) |
| Chroma | moderately saturated (0.114) |
| Temperature | cool |
| Nearest name | Cool Blue (#4984B8) |
| Black text | 4.99:1 |
| White text | 4.20:1 |
Values
| HEX | #577BC0 |
| RGB | rgb(87, 123, 192) |
| HSL | hsl(219, 45%, 55%) |
| OKLCH | oklch(58.7% 0.114 262.5) |
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 #577BC0 | 4.20:1 | AA large text | Lc -74.3 | Content text, not long reading |
| Black text on #577BC0 | 4.99:1 | AA | Lc 35.3 | Non-text elements, placeholder text |
| #577BC0 text on white | 4.20:1 | AA large text | Lc 68.8 | Content text, not long reading |
| #577BC0 text on black | 4.99:1 | AA | Lc -32.8 | 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
#F3F5FA
oklch(97% 0.007 268.5)
-
Step 100
100
#E5EAF4
oklch(93.6% 0.015 264.5)
-
Step 200
200
#CFDAED
oklch(88.6% 0.029 261.5)
-
Step 300
300
#AFC1E3
oklch(80.9% 0.052 263.1)
-
Step 400
400
#85A1D4
oklch(70.7% 0.081 262.2)
-
Step 500
500
#6789C9
oklch(63.2% 0.104 262.4)
-
Step 600
600 (this color)
#577BC0
oklch(58.7% 0.114 262.5)
-
Step 700
700
#3F5F9D
oklch(49.1% 0.107 262.5)
-
Step 800
800
#344E7F
oklch(42.8% 0.088 262.1)
-
Step 900
900
#2E4166
oklch(37.7% 0.068 262.8)
-
Step 950
950
#1B263C
oklch(27% 0.044 263.4)
#577BC0 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) | #5F81C3 | 0.020 |
| Deuteranopia (no green cones) | #5277BF | 0.013 |
| Tritanopia (no blue cones) | #1A8A94 | 0.103 |
| Achromatopsia (no color) | #7C7C7C | 0.114 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #577BC0
#577BC0
oklch(58.7% 0.114 262.5)
- #9D7516
#9D7516
oklch(58.7% 0.114 83)
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 #577BC0, closest first.
No curated palette has a color within ΔE 0.04 of #577BC0.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cool Blue #4984B8 ΔE 0.033
- Windows Blue #3778BF ΔE 0.034
- Steel Blue #4682B4 ΔE 0.034
- Off Blue #5684AE ΔE 0.043
- Dusty Blue #5A86AD ΔE 0.049
- Water Blue #0E87CC ΔE 0.052
- Flat Blue #3C73A8 ΔE 0.053
- Faded Blue #658CBB ΔE 0.055
Use #577BC0 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.