#537BB3
Closest named color: Steel Blue (#4682B4). oklch(57.8% 0.098 256.9), rgb(83, 123, 179).
Aa
Black text reads best on this color (4.85:1).
About this color
#537BB3 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 58%, its chroma 0.098 and its hue 257°. Its hue sits on the cool side of the wheel. The nearest named color is Steel Blue (#4682B4), ΔE 0.022 away. Black text reads best on it, at 4.85:1.
| Hue family | Blues |
| Lightness | medium-dark (58%) |
| Chroma | moderately saturated (0.098) |
| Temperature | cool |
| Nearest name | Steel Blue (#4682B4) |
| Black text | 4.85:1 |
| White text | 4.32:1 |
Values
| HEX | #537BB3 |
| RGB | rgb(83, 123, 179) |
| HSL | hsl(215, 39%, 51%) |
| OKLCH | oklch(57.8% 0.098 256.9) |
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 #537BB3 | 4.32:1 | AA large text | Lc -75.3 | Fine for body text |
| Black text on #537BB3 | 4.85:1 | AA | Lc 34.2 | Non-text elements, placeholder text |
| #537BB3 text on white | 4.32:1 | AA large text | Lc 69.8 | Content text, not long reading |
| #537BB3 text on black | 4.85:1 | AA | Lc -31.8 | 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
#F3F6F9
oklch(97.2% 0.005 247.9)
-
Step 100
100
#E5EAF3
oklch(93.6% 0.013 262.4)
-
Step 200
200
#CFDAEA
oklch(88.5% 0.025 257.6)
-
Step 300
300
#AFC2DD
oklch(80.8% 0.044 257.1)
-
Step 400
400
#85A3CD
oklch(70.8% 0.07 256.8)
-
Step 500
500
#668BC0
oklch(63.1% 0.091 257.4)
-
Step 600
600 (this color)
#537BB3
oklch(57.8% 0.098 256.9)
-
Step 700
700
#3E6294
oklch(49.2% 0.091 256.8)
-
Step 800
800
#335078
oklch(42.8% 0.075 256.7)
-
Step 900
900
#2D4261
oklch(37.6% 0.06 258)
-
Step 950
950
#1B2739
oklch(27.1% 0.038 258.3)
#537BB3 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) | #657EB5 | 0.024 |
| Deuteranopia (no green cones) | #5975B2 | 0.017 |
| Tritanopia (no blue cones) | #1E878F | 0.086 |
| Achromatopsia (no color) | #797979 | 0.098 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #537BB3
#537BB3
oklch(57.8% 0.098 256.9)
- #9A712E
#9A712E
oklch(57.7% 0.098 76.7)
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 #537BB3, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Steel Blue #4682B4 ΔE 0.022
- Cool Blue #4984B8 ΔE 0.025
- Off Blue #5684AE ΔE 0.030
- Windows Blue #3778BF ΔE 0.034
- Stormy Blue #507B9C ΔE 0.037
- Dusty Blue #5A86AD ΔE 0.037
- Flat Blue #3C73A8 ΔE 0.038
- Cerulean #457B9D ΔE 0.039
Use #537BB3 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.