#399AFB
Closest named color: Chefchaouen Blue (#4895EF). oklch(67.7% 0.169 251.9), rgb(57, 154, 251).
Aa
Black text reads best on this color (7.18:1).
About this color
#399AFB is a medium-light, vivid blue. In OKLCH its lightness is 68%, its chroma 0.169 and its hue 252°. 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 7.18:1.
| Hue family | Blues |
| Lightness | medium-light (68%) |
| Chroma | vivid (0.169) |
| Temperature | cool |
| Nearest name | Chefchaouen Blue (#4895EF) |
| Black text | 7.18:1 |
| White text | 2.92:1 |
Values
| HEX | #399AFB |
| RGB | rgb(57, 154, 251) |
| HSL | hsl(210, 96%, 60%) |
| OKLCH | oklch(67.7% 0.169 251.9) |
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 #399AFB | 2.92:1 | Fails | Lc -60.5 | Content text, not long reading |
| Black text on #399AFB | 7.18:1 | AAA | Lc 48.9 | Large or bold text, headings |
| #399AFB text on white | 2.92:1 | Fails | Lc 55.2 | Large or bold text, headings |
| #399AFB text on black | 7.18:1 | AAA | Lc -46.6 | 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
#EFF6FF
oklch(97% 0.014 254.6)
-
Step 100
100
#DCECFE
oklch(93.7% 0.03 251.3)
-
Step 200
200
#BEDCFF
oklch(88.4% 0.058 252.4)
-
Step 300
300
#91C5FF
oklch(80.9% 0.099 251.8)
-
Step 400
400 (this color)
#399AFB
oklch(67.7% 0.169 251.9)
-
Step 500
500
#008AF6
oklch(63% 0.189 252)
-
Step 600
600
#0074D0
oklch(55.6% 0.166 251.9)
-
Step 700
700
#0061B0
oklch(49% 0.147 252)
-
Step 800
800
#005091
oklch(42.8% 0.126 251.5)
-
Step 900
900
#00427A
oklch(37.7% 0.112 251.7)
-
Step 950
950
#00274C
oklch(27.1% 0.08 251.6)
#399AFB 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) | #6CA1FF | 0.049 |
| Deuteranopia (no green cones) | #4C8FF9 | 0.029 |
| Tritanopia (no blue cones) | #00B1BE | 0.126 |
| Achromatopsia (no color) | #979797 | 0.169 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #399AFB
#399AFB
oklch(67.7% 0.169 251.9)
- #CD8600
#CD8600
oklch(67.7% 0.145 72.1)
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 #399AFB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Chefchaouen Blue #4895EF ΔE 0.021
- Dodger Blue #1E90FF ΔE 0.033
- Cornflower Blue #6495ED ΔE 0.038
- Dark Sky Blue #448EE4 ΔE 0.042
- Soft Blue #6488EA ΔE 0.055
- Periwinkle Blue #8F99FB ΔE 0.084
- Clear Blue #247AFD ΔE 0.087
- Water Blue #0E87CC ΔE 0.087
Use #399AFB 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.