#399DD4
Closest named color: Chefchaouen Blue (#4895EF). oklch(66.2% 0.122 237.1), rgb(57, 157, 212).
Aa
Black text reads best on this color (6.94:1).
About this color
#399DD4 is a medium-light, moderately saturated blue. In OKLCH its lightness is 66%, its chroma 0.122 and its hue 237°. Its hue sits on the cool side of the wheel. The nearest named color is Chefchaouen Blue (#4895EF), ΔE 0.052 away. Black text reads best on it, at 6.94:1.
| Hue family | Blues |
| Lightness | medium-light (66%) |
| Chroma | moderately saturated (0.122) |
| Temperature | cool |
| Nearest name | Chefchaouen Blue (#4895EF) |
| Black text | 6.94:1 |
| White text | 3.02:1 |
Values
| HEX | #399DD4 |
| RGB | rgb(57, 157, 212) |
| HSL | hsl(201, 64%, 53%) |
| OKLCH | oklch(66.2% 0.122 237.1) |
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 #399DD4 | 3.02:1 | AA large text | Lc -62.0 | Content text, not long reading |
| Black text on #399DD4 | 6.94:1 | AA | Lc 47.4 | Large or bold text, headings |
| #399DD4 text on white | 3.02:1 | AA large text | Lc 56.6 | Large or bold text, headings |
| #399DD4 text on black | 6.94:1 | AA | Lc -45.1 | 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 500.
-
Step 50
50
#F1F6FA
oklch(97.1% 0.008 241.7)
-
Step 100
100
#E0ECF4
oklch(93.6% 0.017 236.7)
-
Step 200
200
#C6DDED
oklch(88.5% 0.033 238.2)
-
Step 300
300
#9DC7E3
oklch(80.9% 0.06 237.7)
-
Step 400
400
#63AAD5
oklch(70.8% 0.095 236.8)
-
Step 500
500 (this color)
#399DD4
oklch(66.2% 0.122 237.1)
-
Step 600
600
#007CB1
oklch(55.6% 0.122 237.2)
-
Step 700
700
#006896
oklch(49.1% 0.108 237.6)
-
Step 800
800
#00557B
oklch(42.6% 0.093 237.2)
-
Step 900
900
#054766
oklch(37.7% 0.079 236.7)
-
Step 950
950
#082A3C
oklch(27.1% 0.051 236.4)
#399DD4 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) | #839DD7 | 0.070 |
| Deuteranopia (no green cones) | #6E8ED3 | 0.057 |
| Tritanopia (no blue cones) | #00ABB0 | 0.079 |
| Achromatopsia (no color) | #949494 | 0.122 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #399DD4
#399DD4
oklch(66.2% 0.122 237.1)
- #CA7E41
#CA7E41
oklch(66.2% 0.121 57.2)
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 #399DD4, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Chefchaouen Blue #4895EF ΔE 0.052
- Dark Sky Blue #448EE4 ΔE 0.053
- Faded Blue #658CBB ΔE 0.058
- Cornflower Blue #6495ED ΔE 0.060
- Water Blue #0E87CC ΔE 0.068
- Turquoise Blue #06B1C4 ΔE 0.069
- Cool Blue #4984B8 ΔE 0.072
- Greyblue #77A1B5 ΔE 0.073
Use #399DD4 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.