#537CCB
Closest named color: Windows Blue (#3778BF). oklch(59.3% 0.13 262.4), rgb(83, 124, 203).
Aa
Black text reads best on this color (5.11:1).
About this color
#537CCB is a medium-dark, moderately saturated blue. In OKLCH its lightness is 59%, its chroma 0.130 and its hue 262°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.036 away. Black text reads best on it, at 5.11:1.
| Hue family | Blues |
| Lightness | medium-dark (59%) |
| Chroma | moderately saturated (0.130) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 5.11:1 |
| White text | 4.10:1 |
Values
| HEX | #537CCB |
| RGB | rgb(83, 124, 203) |
| HSL | hsl(219, 54%, 56%) |
| OKLCH | oklch(59.3% 0.13 262.4) |
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 #537CCB | 4.10:1 | AA large text | Lc -73.5 | Content text, not long reading |
| Black text on #537CCB | 5.11:1 | AA | Lc 36.1 | Non-text elements, placeholder text |
| #537CCB text on white | 4.10:1 | AA large text | Lc 68.0 | Content text, not long reading |
| #537CCB text on black | 5.11:1 | AA | Lc -33.6 | 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
#F3F6FB
oklch(97.2% 0.007 260.7)
-
Step 100
100
#E4EAF6
oklch(93.6% 0.017 264.5)
-
Step 200
200
#CEDAEF
oklch(88.6% 0.032 261.7)
-
Step 300
300
#ADC1E7
oklch(80.9% 0.058 263.2)
-
Step 400
400
#81A1DB
oklch(70.8% 0.093 262)
-
Step 500
500
#6288D2
oklch(63.1% 0.12 262.8)
-
Step 600
600 (this color)
#537CCB
oklch(59.3% 0.13 262.4)
-
Step 700
700
#3A5EA4
oklch(49.1% 0.12 262.3)
-
Step 800
800
#304D85
oklch(42.7% 0.1 262.3)
-
Step 900
900
#2A416B
oklch(37.8% 0.078 261.6)
-
Step 950
950
#19263F
oklch(27% 0.05 262.6)
#537CCB 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) | #5A83CE | 0.022 |
| Deuteranopia (no green cones) | #4A78C9 | 0.016 |
| Tritanopia (no blue cones) | #008E9A | 0.113 |
| Achromatopsia (no color) | #7D7D7D | 0.130 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #537CCB
#537CCB
oklch(59.3% 0.13 262.4)
- #A27600
#A27600
oklch(59.4% 0.122 82.4)
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 #537CCB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.036
- Cool Blue #4984B8 ΔE 0.042
- Steel Blue #4682B4 ΔE 0.045
- Water Blue #0E87CC ΔE 0.048
- Dark Sky Blue #448EE4 ΔE 0.055
- Off Blue #5684AE ΔE 0.055
- Soft Blue #6488EA ΔE 0.058
- Dusty Blue #5A86AD ΔE 0.061
Use #537CCB 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.