#2566DC
Closest named color: Royal Blue (#4169E1). oklch(54% 0.192 261.2), rgb(37, 102, 220).
Aa
White text reads best on this color (5.23:1).
About this color
#2566DC is a medium-dark, vivid blue. In OKLCH its lightness is 54%, its chroma 0.192 and its hue 261°. Its hue sits on the cool side of the wheel. The nearest named color is Royal Blue (#4169E1), ΔE 0.027 away. White text reads best on it, at 5.23:1.
| Hue family | Blues |
| Lightness | medium-dark (54%) |
| Chroma | vivid (0.192) |
| Temperature | cool |
| Nearest name | Royal Blue (#4169E1) |
| Black text | 4.01:1 |
| White text | 5.23:1 |
Values
| HEX | #2566DC |
| RGB | rgb(37, 102, 220) |
| HSL | hsl(219, 72%, 50%) |
| OKLCH | oklch(54% 0.192 261.2) |
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 #2566DC | 5.23:1 | AA | Lc -80.7 | Fine for body text |
| Black text on #2566DC | 4.01:1 | AA large text | Lc 28.7 | Dividers and decoration only |
| #2566DC text on white | 5.23:1 | AA | Lc 75.4 | Fine for body text |
| #2566DC text on black | 4.01:1 | AA large text | Lc -26.4 | 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
#F1F6FE
oklch(97.2% 0.012 259.8)
-
Step 100
100
#E1EAFB
oklch(93.5% 0.025 263.3)
-
Step 200
200
#C8DAFA
oklch(88.5% 0.048 262)
-
Step 300
300
#A1C2F9
oklch(81% 0.086 260.5)
-
Step 400
400
#6E9FF6
oklch(70.6% 0.139 261.2)
-
Step 500
500
#4885F3
oklch(63.2% 0.177 261.1)
-
Step 600
600 (this color)
#2566DC
oklch(54% 0.192 261.2)
-
Step 700
700
#1D58C4
oklch(49% 0.18 261.3)
-
Step 800
800
#1A499E
oklch(42.7% 0.148 261.1)
-
Step 900
900
#1B3E7E
oklch(37.7% 0.116 261.2)
-
Step 950
950
#11254A
oklch(27.1% 0.074 261.5)
#2566DC 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) | #0075E0 | 0.037 |
| Deuteranopia (no green cones) | #0064DA | 0.016 |
| Tritanopia (no blue cones) | #008397 | 0.148 |
| Achromatopsia (no color) | #6C6C6C | 0.193 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #2566DC
#2566DC
oklch(54% 0.192 261.2)
- #8F6700
#8F6700
oklch(54.1% 0.111 81.8)
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 #2566DC, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Royal Blue #4169E1 ΔE 0.027
- Cerulean Blue #056EEE ΔE 0.033
- Azul #1D5DEC ΔE 0.034
- Neon Blue #4361EE ΔE 0.039
- Warm Blue #4B57DB ΔE 0.044
- Bright Blue #0165FC ΔE 0.050
- Mid Blue #276AB3 ΔE 0.066
- Clear Blue #247AFD ΔE 0.068
Use #2566DC 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.