#4373D1
Closest named color: Windows Blue (#3778BF). oklch(57% 0.154 262.3), rgb(67, 115, 209).
Aa
Black text reads best on this color (4.61:1).
About this color
#4373D1 is a medium-dark, vivid blue. In OKLCH its lightness is 57%, its chroma 0.154 and its hue 262°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.035 away. Black text reads best on it, at 4.61:1.
| Hue family | Blues |
| Lightness | medium-dark (57%) |
| Chroma | vivid (0.154) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 4.61:1 |
| White text | 4.55:1 |
Values
| HEX | #4373D1 |
| RGB | rgb(67, 115, 209) |
| HSL | hsl(220, 61%, 54%) |
| OKLCH | oklch(57% 0.154 262.3) |
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 #4373D1 | 4.55:1 | AA | Lc -76.8 | Fine for body text |
| Black text on #4373D1 | 4.61:1 | AA | Lc 32.8 | Non-text elements, placeholder text |
| #4373D1 text on white | 4.55:1 | AA | Lc 71.3 | Content text, not long reading |
| #4373D1 text on black | 4.61:1 | AA | Lc -30.4 | 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
#F2F6FC
oklch(97.2% 0.009 258.3)
-
Step 100
100
#E3EAF8
oklch(93.6% 0.02 264.5)
-
Step 200
200
#CCDAF3
oklch(88.6% 0.038 262.1)
-
Step 300
300
#A9C1EE
oklch(80.8% 0.069 262.9)
-
Step 400
400
#7BA0E6
oklch(70.7% 0.111 262.5)
-
Step 500
500
#5987DF
oklch(63.2% 0.142 262.2)
-
Step 600
600 (this color)
#4373D1
oklch(57% 0.154 262.3)
-
Step 700
700
#315CB1
oklch(49.1% 0.144 262.3)
-
Step 800
800
#294C8F
oklch(42.8% 0.118 261.9)
-
Step 900
900
#264072
oklch(37.8% 0.092 262.2)
-
Step 950
950
#162643
oklch(27.1% 0.058 261.5)
#4373D1 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) | #447DD5 | 0.027 |
| Deuteranopia (no green cones) | #2A70CF | 0.023 |
| Tritanopia (no blue cones) | #008998 | 0.125 |
| Achromatopsia (no color) | #767676 | 0.154 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #4373D1
#4373D1
oklch(57% 0.154 262.3)
- #996F00
#996F00
oklch(56.9% 0.117 82.2)
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 #4373D1, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.035
- Royal Blue #4169E1 ΔE 0.038
- French Blue #436BAD ΔE 0.057
- Cerulean Blue #056EEE ΔE 0.058
- Mid Blue #276AB3 ΔE 0.058
- Water Blue #0E87CC ΔE 0.059
- Dark Periwinkle #665FD1 ΔE 0.061
- Neon Blue #4361EE ΔE 0.065
Use #4373D1 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.