#3370E1
Closest named color: Royal Blue (#4169E1). oklch(56.9% 0.184 261.4), rgb(51, 112, 225).
Aa
White text reads best on this color (4.61:1).
About this color
#3370E1 is a medium-dark, vivid blue. In OKLCH its lightness is 57%, its chroma 0.184 and its hue 261°. Its hue sits on the cool side of the wheel. The nearest named color is Royal Blue (#4169E1), ΔE 0.019 away. White text reads best on it, at 4.61:1.
| Hue family | Blues |
| Lightness | medium-dark (57%) |
| Chroma | vivid (0.184) |
| Temperature | cool |
| Nearest name | Royal Blue (#4169E1) |
| Black text | 4.54:1 |
| White text | 4.61:1 |
Values
| HEX | #3370E1 |
| RGB | rgb(51, 112, 225) |
| HSL | hsl(219, 74%, 54%) |
| OKLCH | oklch(56.9% 0.184 261.4) |
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 #3370E1 | 4.61:1 | AA | Lc -77.1 | Fine for body text |
| Black text on #3370E1 | 4.54:1 | AA | Lc 32.5 | Non-text elements, placeholder text |
| #3370E1 text on white | 4.61:1 | AA | Lc 71.6 | Content text, not long reading |
| #3370E1 text on black | 4.54:1 | AA | Lc -30.1 | 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
#F1F6FD
oklch(97.1% 0.011 256.7)
-
Step 100
100
#E1EAFA
oklch(93.5% 0.024 262.1)
-
Step 200
200
#C9DAF8
oklch(88.5% 0.045 261.9)
-
Step 300
300
#A3C2F7
oklch(81% 0.083 261)
-
Step 400
400
#71A0F3
oklch(70.8% 0.132 261.2)
-
Step 500
500
#4C85EE
oklch(63% 0.169 261.4)
-
Step 600
600 (this color)
#3370E1
oklch(56.9% 0.184 261.4)
-
Step 700
700
#2259C0
oklch(49% 0.172 261.5)
-
Step 800
800
#1E4A9B
oklch(42.8% 0.141 261.3)
-
Step 900
900
#1E3F7B
oklch(37.8% 0.109 261.2)
-
Step 950
950
#122548
oklch(27% 0.07 261.5)
#3370E1 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) | #287DE5 | 0.033 |
| Deuteranopia (no green cones) | #006DDF | 0.025 |
| Tritanopia (no blue cones) | #008B9E | 0.142 |
| Achromatopsia (no color) | #757575 | 0.184 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3370E1
#3370E1
oklch(56.9% 0.184 261.4)
- #9A6E00
#9A6E00
oklch(56.8% 0.117 80.8)
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 #3370E1, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Royal Blue #4169E1 ΔE 0.019
- Cerulean Blue #056EEE ΔE 0.029
- Neon Blue #4361EE ΔE 0.042
- Clear Blue #247AFD ΔE 0.047
- Azul #1D5DEC ΔE 0.054
- Bright Blue #0165FC ΔE 0.055
- Windows Blue #3778BF ΔE 0.060
- Warm Blue #4B57DB ΔE 0.060
Use #3370E1 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.