#399FDE
Closest named color: Chefchaouen Blue (#4895EF). oklch(67.2% 0.131 240.3), rgb(57, 159, 222).
Aa
Black text reads best on this color (7.18:1).
About this color
#399FDE is a medium-light, moderately saturated blue. In OKLCH its lightness is 67%, its chroma 0.131 and its hue 240°. Its hue sits on the cool side of the wheel. The nearest named color is Chefchaouen Blue (#4895EF), ΔE 0.042 away. Black text reads best on it, at 7.18:1.
| Hue family | Blues |
| Lightness | medium-light (67%) |
| Chroma | moderately saturated (0.131) |
| Temperature | cool |
| Nearest name | Chefchaouen Blue (#4895EF) |
| Black text | 7.18:1 |
| White text | 2.92:1 |
Values
| HEX | #399FDE |
| RGB | rgb(57, 159, 222) |
| HSL | hsl(203, 71%, 55%) |
| OKLCH | oklch(67.2% 0.131 240.3) |
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 #399FDE | 2.92:1 | Fails | Lc -60.6 | Content text, not long reading |
| Black text on #399FDE | 7.18:1 | AAA | Lc 48.8 | Large or bold text, headings |
| #399FDE text on white | 2.92:1 | Fails | Lc 55.3 | Large or bold text, headings |
| #399FDE text on black | 7.18:1 | AAA | Lc -46.5 | Large or bold text, headings |
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 400.
-
Step 50
50
#EFF7FC
oklch(97.2% 0.011 234.8)
-
Step 100
100
#DCECF8
oklch(93.5% 0.024 240.1)
-
Step 200
200
#BFDEF5
oklch(88.5% 0.046 240.2)
-
Step 300
300
#90C8F1
oklch(80.9% 0.082 240.8)
-
Step 400
400 (this color)
#399FDE
oklch(67.2% 0.131 240.3)
-
Step 500
500
#0092D8
oklch(63% 0.146 240.6)
-
Step 600
600
#007BB6
oklch(55.6% 0.128 240.2)
-
Step 700
700
#00679A
oklch(49.1% 0.113 240.5)
-
Step 800
800
#00547F
oklch(42.6% 0.099 240.7)
-
Step 900
900
#00466B
oklch(37.7% 0.087 240.8)
-
Step 950
950
#002942
oklch(26.9% 0.063 241.6)
#399FDE 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) | #82A0E1 | 0.068 |
| Deuteranopia (no green cones) | #6B90DD | 0.054 |
| Tritanopia (no blue cones) | #00AFB5 | 0.089 |
| Achromatopsia (no color) | #979797 | 0.131 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #399FDE
#399FDE
oklch(67.2% 0.131 240.3)
- #CF8036
#CF8036
oklch(67.1% 0.131 60.2)
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 #399FDE, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Chefchaouen Blue #4895EF ΔE 0.042
- Dark Sky Blue #448EE4 ΔE 0.049
- Cornflower Blue #6495ED ΔE 0.051
- Faded Blue #658CBB ΔE 0.068
- Dodger Blue #1E90FF ΔE 0.072
- Soft Blue #6488EA ΔE 0.073
- Turquoise Blue #06B1C4 ΔE 0.074
- Water Blue #0E87CC ΔE 0.074
Use #399FDE 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.