#1C66E8
Closest named color: Cerulean Blue (#056EEE). oklch(54.8% 0.21 261), rgb(28, 102, 232).
Aa
White text reads best on this color (5.10:1).
About this color
#1C66E8 is a medium-dark, vivid blue. In OKLCH its lightness is 55%, its chroma 0.210 and its hue 261°. Its hue sits on the cool side of the wheel. The nearest named color is Cerulean Blue (#056EEE), ΔE 0.020 away. White text reads best on it, at 5.10:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | vivid (0.210) |
| Temperature | cool |
| Nearest name | Cerulean Blue (#056EEE) |
| Black text | 4.11:1 |
| White text | 5.10:1 |
Values
| HEX | #1C66E8 |
| RGB | rgb(28, 102, 232) |
| HSL | hsl(218, 82%, 51%) |
| OKLCH | oklch(54.8% 0.21 261) |
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 #1C66E8 | 5.10:1 | AA | Lc -79.9 | Fine for body text |
| Black text on #1C66E8 | 4.11:1 | AA large text | Lc 29.6 | Dividers and decoration only |
| #1C66E8 text on white | 5.10:1 | AA | Lc 74.4 | Content text, not long reading |
| #1C66E8 text on black | 4.11:1 | AA large text | Lc -27.3 | 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
#E0EBFD
oklch(93.7% 0.027 260.3)
-
Step 200
200
#C6DAFD
oklch(88.5% 0.053 261.7)
-
Step 300
300
#9EC2FE
oklch(81% 0.094 260.4)
-
Step 400
400
#699FFE
oklch(70.7% 0.151 261)
-
Step 500
500
#4083FC
oklch(63.1% 0.193 261.1)
-
Step 600
600 (this color)
#1C66E8
oklch(54.8% 0.21 261)
-
Step 700
700
#1256CC
oklch(49% 0.194 261.1)
-
Step 800
800
#1247A5
oklch(42.6% 0.161 261.1)
-
Step 900
900
#163D83
oklch(37.7% 0.126 261)
-
Step 950
950
#0E244D
oklch(26.9% 0.081 261.5)
#1C66E8 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) | #0077EC | 0.041 |
| Deuteranopia (no green cones) | #0065E5 | 0.011 |
| Tritanopia (no blue cones) | #00879D | 0.160 |
| Achromatopsia (no color) | #6E6E6E | 0.210 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1C66E8
#1C66E8
oklch(54.8% 0.21 261)
- #926800
#926800
oklch(54.6% 0.113 80.7)
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 #1C66E8, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cerulean Blue #056EEE ΔE 0.020
- Azul #1D5DEC ΔE 0.022
- Royal Blue #4169E1 ΔE 0.031
- Bright Blue #0165FC ΔE 0.031
- Neon Blue #4361EE ΔE 0.031
- Warm Blue #4B57DB ΔE 0.050
- Electric Blue #0652FF ΔE 0.057
- Clear Blue #247AFD ΔE 0.058
Use #1C66E8 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.