#537BBF
Closest named color: Windows Blue (#3778BF). oklch(58.4% 0.114 260.5), rgb(83, 123, 191).
Aa
Black text reads best on this color (4.95:1).
About this color
#537BBF is a medium-dark, moderately saturated blue. In OKLCH its lightness is 58%, its chroma 0.114 and its hue 260°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.029 away. Black text reads best on it, at 4.95:1.
| Hue family | Blues |
| Lightness | medium-dark (58%) |
| Chroma | moderately saturated (0.114) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 4.95:1 |
| White text | 4.23:1 |
Values
| HEX | #537BBF |
| RGB | rgb(83, 123, 191) |
| HSL | hsl(218, 46%, 54%) |
| OKLCH | oklch(58.4% 0.114 260.5) |
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 #537BBF | 4.23:1 | AA large text | Lc -74.6 | Content text, not long reading |
| Black text on #537BBF | 4.95:1 | AA | Lc 35.0 | Non-text elements, placeholder text |
| #537BBF text on white | 4.23:1 | AA large text | Lc 69.1 | Content text, not long reading |
| #537BBF text on black | 4.95:1 | AA | Lc -32.5 | 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
#E4EAF4
oklch(93.5% 0.015 260.7)
-
Step 200
200
#CEDAED
oklch(88.5% 0.029 259.6)
-
Step 300
300
#AEC2E3
oklch(81% 0.052 260.4)
-
Step 400
400
#83A2D4
oklch(70.8% 0.081 259.8)
-
Step 500
500
#648AC9
oklch(63.2% 0.105 260.2)
-
Step 600
600 (this color)
#537BBF
oklch(58.4% 0.114 260.5)
-
Step 700
700
#3C609C
oklch(49.1% 0.105 260.1)
-
Step 800
800
#324E7F
oklch(42.6% 0.089 260.9)
-
Step 900
900
#2C4166
oklch(37.6% 0.069 261.2)
-
Step 950
950
#1A263C
oklch(26.9% 0.045 261.9)
#537BBF 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) | #5F80C2 | 0.021 |
| Deuteranopia (no green cones) | #5276BE | 0.014 |
| Tritanopia (no blue cones) | #018A94 | 0.102 |
| Achromatopsia (no color) | #7B7B7B | 0.114 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #537BBF
#537BBF
oklch(58.4% 0.114 260.5)
- #9E7315
#9E7315
oklch(58.4% 0.114 80.8)
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 #537BBF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.029
- Cool Blue #4984B8 ΔE 0.031
- Steel Blue #4682B4 ΔE 0.031
- Off Blue #5684AE ΔE 0.042
- Dusty Blue #5A86AD ΔE 0.048
- Flat Blue #3C73A8 ΔE 0.049
- Water Blue #0E87CC ΔE 0.049
- French Blue #436BAD ΔE 0.054
Use #537BBF 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.