#4273EA
Closest named color: Royal Blue (#4169E1). oklch(58.7% 0.188 264.5), rgb(66, 115, 234).
Aa
Black text reads best on this color (4.87:1).
About this color
#4273EA is a medium-dark, vivid blue. In OKLCH its lightness is 59%, its chroma 0.188 and its hue 264°. Its hue sits on the cool side of the wheel. The nearest named color is Royal Blue (#4169E1), ΔE 0.028 away. Black text reads best on it, at 4.87:1.
| Hue family | Blues |
| Lightness | medium-dark (59%) |
| Chroma | vivid (0.188) |
| Temperature | cool |
| Nearest name | Royal Blue (#4169E1) |
| Black text | 4.87:1 |
| White text | 4.31:1 |
Values
| HEX | #4273EA |
| RGB | rgb(66, 115, 234) |
| HSL | hsl(223, 80%, 59%) |
| OKLCH | oklch(58.7% 0.188 264.5) |
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 #4273EA | 4.31:1 | AA large text | Lc -74.9 | Content text, not long reading |
| Black text on #4273EA | 4.87:1 | AA | Lc 34.7 | Non-text elements, placeholder text |
| #4273EA text on white | 4.31:1 | AA large text | Lc 69.4 | Content text, not long reading |
| #4273EA text on black | 4.87:1 | AA | Lc -32.3 | 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
#F2F6FD
oklch(97.2% 0.01 261.8)
-
Step 100
100
#E2EAFB
oklch(93.6% 0.025 265.6)
-
Step 200
200
#CAD9F9
oklch(88.4% 0.047 265.5)
-
Step 300
300
#A5C0F8
oklch(80.8% 0.085 264.6)
-
Step 400
400
#769EF5
oklch(70.7% 0.135 264.5)
-
Step 500
500
#5383F1
oklch(63.1% 0.173 264.3)
-
Step 600
600 (this color)
#4273EA
oklch(58.7% 0.188 264.5)
-
Step 700
700
#2C57C2
oklch(49.1% 0.175 264.3)
-
Step 800
800
#25489D
oklch(42.8% 0.145 264.3)
-
Step 900
900
#223D7D
oklch(37.7% 0.114 264.4)
-
Step 950
950
#142449
oklch(26.9% 0.072 264.5)
#4273EA 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) | #2782EE | 0.038 |
| Deuteranopia (no green cones) | #0072E8 | 0.034 |
| Tritanopia (no blue cones) | #008FA4 | 0.148 |
| Achromatopsia (no color) | #7A7A7A | 0.188 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #4273EA
#4273EA
oklch(58.7% 0.188 264.5)
- #9D7500
#9D7500
oklch(58.6% 0.12 84.6)
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 #4273EA, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Royal Blue #4169E1 ΔE 0.028
- Clear Blue #247AFD ΔE 0.035
- Cerulean Blue #056EEE ΔE 0.037
- Neon Blue #4361EE ΔE 0.044
- Cornflower #6A79F7 ΔE 0.053
- Bright Blue #0165FC ΔE 0.059
- Azul #1D5DEC ΔE 0.065
- Dark Periwinkle #665FD1 ΔE 0.067
Use #4273EA 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.