#399CEC
Closest named color: Chefchaouen Blue (#4895EF). oklch(67.3% 0.149 247.1), rgb(57, 156, 236).
Aa
Black text reads best on this color (7.14:1).
About this color
#399CEC is a medium-light, vivid blue. In OKLCH its lightness is 67%, its chroma 0.149 and its hue 247°. Its hue sits on the cool side of the wheel. The nearest named color is Chefchaouen Blue (#4895EF), ΔE 0.021 away. Black text reads best on it, at 7.14:1.
| Hue family | Blues |
| Lightness | medium-light (67%) |
| Chroma | vivid (0.149) |
| Temperature | cool |
| Nearest name | Chefchaouen Blue (#4895EF) |
| Black text | 7.14:1 |
| White text | 2.94:1 |
Values
| HEX | #399CEC |
| RGB | rgb(57, 156, 236) |
| HSL | hsl(207, 82%, 57%) |
| OKLCH | oklch(67.3% 0.149 247.1) |
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 #399CEC | 2.94:1 | Fails | Lc -60.8 | Content text, not long reading |
| Black text on #399CEC | 7.14:1 | AAA | Lc 48.6 | Large or bold text, headings |
| #399CEC text on white | 2.94:1 | Fails | Lc 55.5 | Large or bold text, headings |
| #399CEC text on black | 7.14:1 | AAA | Lc -46.3 | 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
#EFF6FE
oklch(97% 0.013 251.6)
-
Step 100
100
#DCECFB
oklch(93.6% 0.027 246.3)
-
Step 200
200
#BFDDFA
oklch(88.5% 0.051 247.5)
-
Step 300
300
#8FC7FA
oklch(81% 0.093 246.7)
-
Step 400
400 (this color)
#399CEC
oklch(67.3% 0.149 247.1)
-
Step 500
500
#008FE7
oklch(63.2% 0.166 246.8)
-
Step 600
600
#0078C3
oklch(55.7% 0.146 246.8)
-
Step 700
700
#0064A5
oklch(49% 0.13 247.2)
-
Step 800
800
#005288
oklch(42.7% 0.112 246.9)
-
Step 900
900
#004473
oklch(37.7% 0.1 247.4)
-
Step 950
950
#002847
oklch(27% 0.072 247.4)
#399CEC 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) | #77A0EF | 0.057 |
| Deuteranopia (no green cones) | #5D8FEA | 0.040 |
| Tritanopia (no blue cones) | #00AFB9 | 0.107 |
| Achromatopsia (no color) | #969696 | 0.149 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #399CEC
#399CEC
oklch(67.3% 0.149 247.1)
- #D18100
#D18100
oklch(67.3% 0.148 67.3)
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 #399CEC, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Chefchaouen Blue #4895EF ΔE 0.021
- Dark Sky Blue #448EE4 ΔE 0.037
- Cornflower Blue #6495ED ΔE 0.037
- Dodger Blue #1E90FF ΔE 0.049
- Soft Blue #6488EA ΔE 0.059
- Water Blue #0E87CC ΔE 0.075
- Faded Blue #658CBB ΔE 0.079
- Periwinkle Blue #8F99FB ΔE 0.089
Use #399CEC 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.