#5370BB
Closest named color: Windows Blue (#3778BF). oklch(55.8% 0.122 266.6), rgb(83, 112, 187).
Aa
White text reads best on this color (4.76:1).
About this color
#5370BB is a medium-dark, moderately saturated blue. In OKLCH its lightness is 56%, its chroma 0.122 and its hue 267°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.032 away. White text reads best on it, at 4.76:1.
| Hue family | Blues |
| Lightness | medium-dark (56%) |
| Chroma | moderately saturated (0.122) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 4.40:1 |
| White text | 4.76:1 |
Values
| HEX | #5370BB |
| RGB | rgb(83, 112, 187) |
| HSL | hsl(223, 43%, 53%) |
| OKLCH | oklch(55.8% 0.122 266.6) |
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 #5370BB | 4.76:1 | AA | Lc -78.4 | Fine for body text |
| Black text on #5370BB | 4.40:1 | AA large text | Lc 31.1 | Non-text elements, placeholder text |
| #5370BB text on white | 4.76:1 | AA | Lc 72.9 | Content text, not long reading |
| #5370BB text on black | 4.40:1 | AA large text | Lc -28.7 | Dividers and decoration only |
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
#F3F5FB
oklch(97% 0.008 271.3)
-
Step 100
100
#E5EAF5
oklch(93.6% 0.016 266.3)
-
Step 200
200
#D0D9EE
oklch(88.5% 0.031 267.2)
-
Step 300
300
#B0C0E5
oklch(80.8% 0.055 266.7)
-
Step 400
400
#889FD8
oklch(70.7% 0.088 267.2)
-
Step 500
500
#6A87CD
oklch(63.1% 0.111 266.2)
-
Step 600
600 (this color)
#5370BB
oklch(55.8% 0.122 266.6)
-
Step 700
700
#435DA1
oklch(49.2% 0.113 266.5)
-
Step 800
800
#374C82
oklch(42.7% 0.094 266.5)
-
Step 900
900
#304068
oklch(37.8% 0.072 266.5)
-
Step 950
950
#1C263D
oklch(27.1% 0.045 265.6)
#5370BB 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) | #5178BE | 0.021 |
| Deuteranopia (no green cones) | #446EB9 | 0.019 |
| Tritanopia (no blue cones) | #15808C | 0.109 |
| Achromatopsia (no color) | #737373 | 0.122 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #5370BB
#5370BB
oklch(55.8% 0.122 266.6)
- #916E00
#916E00
oklch(55.8% 0.114 86.4)
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 #5370BB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.032
- French Blue #436BAD ΔE 0.032
- Flat Blue #3C73A8 ΔE 0.042
- Mid Blue #276AB3 ΔE 0.049
- Muted Blue #3B719F ΔE 0.054
- Steel Blue #4682B4 ΔE 0.054
- Dull Blue #49759C ΔE 0.056
- Cool Blue #4984B8 ΔE 0.057
Use #5370BB 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.