#577CBF
Closest named color: Cool Blue (#4984B8). oklch(58.9% 0.112 261.6), rgb(87, 124, 191).
Aa
Black text reads best on this color (5.04:1).
About this color
#577CBF is a medium-dark, moderately saturated blue. In OKLCH its lightness is 59%, its chroma 0.112 and its hue 262°. Its hue sits on the cool side of the wheel. The nearest named color is Cool Blue (#4984B8), ΔE 0.030 away. Black text reads best on it, at 5.04:1.
| Hue family | Blues |
| Lightness | medium-dark (59%) |
| Chroma | moderately saturated (0.112) |
| Temperature | cool |
| Nearest name | Cool Blue (#4984B8) |
| Black text | 5.04:1 |
| White text | 4.16:1 |
Values
| HEX | #577CBF |
| RGB | rgb(87, 124, 191) |
| HSL | hsl(219, 45%, 55%) |
| OKLCH | oklch(58.9% 0.112 261.6) |
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 #577CBF | 4.16:1 | AA large text | Lc -74.1 | Content text, not long reading |
| Black text on #577CBF | 5.04:1 | AA | Lc 35.5 | Non-text elements, placeholder text |
| #577CBF text on white | 4.16:1 | AA large text | Lc 68.6 | Content text, not long reading |
| #577CBF text on black | 5.04:1 | AA | Lc -33.1 | 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 600.
-
Step 50
50
#F3F6FA
oklch(97.2% 0.006 255.5)
-
Step 100
100
#E5EAF4
oklch(93.6% 0.015 264.5)
-
Step 200
200
#CFDAEC
oklch(88.5% 0.028 260.3)
-
Step 300
300
#AFC1E2
oklch(80.8% 0.051 262.6)
-
Step 400
400
#85A1D3
oklch(70.7% 0.08 261.8)
-
Step 500
500
#6689C8
oklch(63.1% 0.103 261.6)
-
Step 600
600 (this color)
#577CBF
oklch(58.9% 0.112 261.6)
-
Step 700
700
#3F5F9B
oklch(49% 0.104 262)
-
Step 800
800
#344E7E
oklch(42.7% 0.086 261.8)
-
Step 900
900
#2D4165
oklch(37.6% 0.067 261.5)
-
Step 950
950
#1B263B
oklch(26.9% 0.042 262.7)
#577CBF 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) | #6181C2 | 0.020 |
| Deuteranopia (no green cones) | #5478BE | 0.012 |
| Tritanopia (no blue cones) | #1B8B94 | 0.101 |
| Achromatopsia (no color) | #7C7C7C | 0.112 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #577CBF
#577CBF
oklch(58.9% 0.112 261.6)
- #9E751D
#9E751D
oklch(58.9% 0.111 81.5)
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 #577CBF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cool Blue #4984B8 ΔE 0.030
- Steel Blue #4682B4 ΔE 0.031
- Windows Blue #3778BF ΔE 0.035
- Off Blue #5684AE ΔE 0.039
- Dusty Blue #5A86AD ΔE 0.045
- Water Blue #0E87CC ΔE 0.051
- Faded Blue #658CBB ΔE 0.052
- Flat Blue #3C73A8 ΔE 0.053
Use #577CBF 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.