#2399D1
Closest named color: Dark Sky Blue (#448EE4). oklch(64.7% 0.128 235.5), rgb(35, 153, 209).
Aa
Black text reads best on this color (6.54:1).
About this color
#2399D1 is a medium-light, moderately saturated blue. In OKLCH its lightness is 65%, its chroma 0.128 and its hue 236°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Sky Blue (#448EE4), ΔE 0.049 away. Black text reads best on it, at 6.54:1.
| Hue family | Blues |
| Lightness | medium-light (65%) |
| Chroma | moderately saturated (0.128) |
| Temperature | cool |
| Nearest name | Dark Sky Blue (#448EE4) |
| Black text | 6.54:1 |
| White text | 3.20:1 |
Values
| HEX | #2399D1 |
| RGB | rgb(35, 153, 209) |
| HSL | hsl(199, 71%, 48%) |
| OKLCH | oklch(64.7% 0.128 235.5) |
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 #2399D1 | 3.20:1 | AA large text | Lc -64.2 | Content text, not long reading |
| Black text on #2399D1 | 6.54:1 | AA | Lc 45.2 | Large or bold text, headings |
| #2399D1 text on white | 3.20:1 | AA large text | Lc 58.8 | Large or bold text, headings |
| #2399D1 text on black | 6.54:1 | AA | Lc -42.9 | Non-text elements, placeholder text |
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
#F0F6FA
oklch(97% 0.008 236.6)
-
Step 100
100
#DFECF5
oklch(93.6% 0.018 237.8)
-
Step 200
200
#C4DDED
oklch(88.4% 0.035 235.9)
-
Step 300
300
#9AC8E4
oklch(81% 0.063 235.3)
-
Step 400
400
#5DAAD7
oklch(70.7% 0.101 236.2)
-
Step 500
500 (this color)
#2399D1
oklch(64.7% 0.128 235.5)
-
Step 600
600
#007DAF
oklch(55.7% 0.119 235.4)
-
Step 700
700
#006994
oklch(49.2% 0.105 235.5)
-
Step 800
800
#00567A
oklch(42.8% 0.091 235.4)
-
Step 900
900
#004766
oklch(37.6% 0.081 235.8)
-
Step 950
950
#052A3D
oklch(27% 0.053 236.3)
#2399D1 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) | #7E98D4 | 0.077 |
| Deuteranopia (no green cones) | #6789D0 | 0.062 |
| Tritanopia (no blue cones) | #00A8AC | 0.081 |
| Achromatopsia (no color) | #909090 | 0.129 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #2399D1
#2399D1
oklch(64.7% 0.128 235.5)
- #C97737
#C97737
oklch(64.7% 0.129 55.6)
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 #2399D1, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Sky Blue #448EE4 ΔE 0.049
- Water Blue #0E87CC ΔE 0.052
- Chefchaouen Blue #4895EF ΔE 0.055
- Faded Blue #658CBB ΔE 0.058
- Blue NCS #118AB2 ΔE 0.059
- Cool Blue #4984B8 ΔE 0.062
- Cornflower Blue #6495ED ΔE 0.068
- Steel Blue #4682B4 ΔE 0.068
Use #2399D1 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.