#5581CF
Closest named color: Cool Blue (#4984B8). oklch(60.7% 0.129 261.1), rgb(85, 129, 207).
Aa
Black text reads best on this color (5.42:1).
About this color
#5581CF is a medium-dark, moderately saturated blue. In OKLCH its lightness is 61%, its chroma 0.129 and its hue 261°. Its hue sits on the cool side of the wheel. The nearest named color is Cool Blue (#4984B8), ΔE 0.041 away. Black text reads best on it, at 5.42:1.
| Hue family | Blues |
| Lightness | medium-dark (61%) |
| Chroma | moderately saturated (0.129) |
| Temperature | cool |
| Nearest name | Cool Blue (#4984B8) |
| Black text | 5.42:1 |
| White text | 3.86:1 |
Values
| HEX | #5581CF |
| RGB | rgb(85, 129, 207) |
| HSL | hsl(218, 56%, 57%) |
| OKLCH | oklch(60.7% 0.129 261.1) |
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 #5581CF | 3.86:1 | AA large text | Lc -71.5 | Content text, not long reading |
| Black text on #5581CF | 5.42:1 | AA | Lc 38.1 | Non-text elements, placeholder text |
| #5581CF text on white | 3.86:1 | AA large text | Lc 66.0 | Content text, not long reading |
| #5581CF text on black | 5.42:1 | AA | Lc -35.7 | 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
#F2F6FB
oklch(97.2% 0.008 253.9)
-
Step 100
100
#E3EAF6
oklch(93.5% 0.018 261.3)
-
Step 200
200
#CCDAF1
oklch(88.5% 0.035 260.4)
-
Step 300
300
#AAC2EA
oklch(81% 0.063 260.6)
-
Step 400
400
#7DA1E0
oklch(70.7% 0.101 261.2)
-
Step 500
500 (this color)
#5581CF
oklch(60.7% 0.129 261.1)
-
Step 600
600
#4271C4
oklch(55.7% 0.139 260.9)
-
Step 700
700
#345EAA
oklch(49.2% 0.131 261.2)
-
Step 800
800
#2B4D89
oklch(42.7% 0.107 260.9)
-
Step 900
900
#27416E
oklch(37.8% 0.084 260.7)
-
Step 950
950
#172640
oklch(27% 0.053 260.8)
#5581CF 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) | #6088D2 | 0.024 |
| Deuteranopia (no green cones) | #507CCD | 0.015 |
| Tritanopia (no blue cones) | #00929E | 0.111 |
| Achromatopsia (no color) | #818181 | 0.129 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #5581CF
#5581CF
oklch(60.7% 0.129 261.1)
- #A87900
#A87900
oklch(60.7% 0.125 81.3)
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 #5581CF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cool Blue #4984B8 ΔE 0.041
- Dark Sky Blue #448EE4 ΔE 0.042
- Water Blue #0E87CC ΔE 0.045
- Windows Blue #3778BF ΔE 0.046
- Steel Blue #4682B4 ΔE 0.047
- Soft Blue #6488EA ΔE 0.047
- Faded Blue #658CBB ΔE 0.052
- Off Blue #5684AE ΔE 0.054
Use #5581CF 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.