#3739EF
Closest named color: Light Royal Blue (#3A2EFE). oklch(48.9% 0.26 271.1), rgb(55, 57, 239).
Aa
White text reads best on this color (7.01:1).
About this color
#3739EF is a medium-dark, vivid blue. In OKLCH its lightness is 49%, its chroma 0.260 and its hue 271°. Its hue sits on the cool side of the wheel. The nearest named color is Light Royal Blue (#3A2EFE), ΔE 0.025 away. White text reads best on it, at 7.01:1.
| Hue family | Blues |
| Lightness | medium-dark (49%) |
| Chroma | vivid (0.260) |
| Temperature | cool |
| Nearest name | Light Royal Blue (#3A2EFE) |
| Black text | 2.99:1 |
| White text | 7.01:1 |
Values
| HEX | #3739EF |
| RGB | rgb(55, 57, 239) |
| HSL | hsl(239, 85%, 58%) |
| OKLCH | oklch(48.9% 0.26 271.1) |
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 #3739EF | 7.01:1 | AAA | Lc -88.0 | Fine for body text |
| Black text on #3739EF | 2.99:1 | Fails | Lc 21.0 | Dividers and decoration only |
| #3739EF text on white | 7.01:1 | AAA | Lc 83.0 | Fine for body text |
| #3739EF text on black | 2.99:1 | Fails | Lc -18.9 | 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 700.
-
Step 50
50
#F2F5FF
oklch(97.1% 0.014 272.7)
-
Step 100
100
#E2E9FF
oklch(93.5% 0.031 271.7)
-
Step 200
200
#CBD8FF
oklch(88.5% 0.056 270.7)
-
Step 300
300
#AABEFF
oklch(81% 0.095 271)
-
Step 400
400
#7E99FF
oklch(70.7% 0.152 270.9)
-
Step 500
500
#607BFF
oklch(63.2% 0.197 271)
-
Step 600
600
#4658FF
oklch(55.6% 0.245 271)
-
Step 700
700 (this color)
#3739EF
oklch(48.9% 0.26 271.1)
-
Step 800
800
#2D33C1
oklch(42.7% 0.214 271.1)
-
Step 900
900
#263098
oklch(37.7% 0.167 271.2)
-
Step 950
950
#151E59
oklch(27% 0.106 270.8)
#3739EF 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) | #0062F4 | 0.078 |
| Deuteranopia (no green cones) | #004FEC | 0.044 |
| Tritanopia (no blue cones) | #007093 | 0.199 |
| Achromatopsia (no color) | #595959 | 0.261 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3739EF
#3739EF
oklch(48.9% 0.26 271.1)
- #755D00
#755D00
oklch(48.8% 0.1 91.2)
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 #3739EF, closest first.
No curated palette has a color within ΔE 0.04 of #3739EF.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Light Royal Blue #3A2EFE ΔE 0.025
- Vibrant Blue #0339F8 ΔE 0.038
- Vivid Blue #152EFF ΔE 0.043
- Electric Blue #0652FF ΔE 0.054
- Purpley Blue #5F34E7 ΔE 0.060
- Rich Blue #021BF9 ΔE 0.061
- Majorelle Blue #3F37C9 ΔE 0.061
- Blue Purple #5A06EF ΔE 0.063
Use #3739EF 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.