#3399D9
Closest named color: Dark Sky Blue (#448EE4). oklch(65.4% 0.132 241.1), rgb(51, 153, 217).
Aa
Black text reads best on this color (6.69:1).
About this color
#3399D9 is a medium-light, moderately saturated blue. In OKLCH its lightness is 65%, its chroma 0.132 and its hue 241°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Sky Blue (#448EE4), ΔE 0.038 away. Black text reads best on it, at 6.69:1.
| Hue family | Blues |
| Lightness | medium-light (65%) |
| Chroma | moderately saturated (0.132) |
| Temperature | cool |
| Nearest name | Dark Sky Blue (#448EE4) |
| Black text | 6.69:1 |
| White text | 3.13:1 |
Values
| HEX | #3399D9 |
| RGB | rgb(51, 153, 217) |
| HSL | hsl(203, 69%, 53%) |
| OKLCH | oklch(65.4% 0.132 241.1) |
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 #3399D9 | 3.13:1 | AA large text | Lc -63.4 | Content text, not long reading |
| Black text on #3399D9 | 6.69:1 | AA | Lc 46.0 | Large or bold text, headings |
| #3399D9 text on white | 3.13:1 | AA large text | Lc 58.0 | Large or bold text, headings |
| #3399D9 text on black | 6.69:1 | AA | Lc -43.7 | 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
#F1F6FB
oklch(97.1% 0.009 247.9)
-
Step 100
100
#DFECF5
oklch(93.6% 0.018 237.8)
-
Step 200
200
#C5DDEF
oklch(88.5% 0.036 240.3)
-
Step 300
300
#9CC7E7
oklch(81% 0.064 240.8)
-
Step 400
400
#61A9DB
oklch(70.8% 0.103 240.6)
-
Step 500
500 (this color)
#3399D9
oklch(65.4% 0.132 241.1)
-
Step 600
600
#007BB8
oklch(55.7% 0.13 241.1)
-
Step 700
700
#00679B
oklch(49.1% 0.115 241)
-
Step 800
800
#005480
oklch(42.6% 0.1 241.3)
-
Step 900
900
#03466B
oklch(37.7% 0.087 241.4)
-
Step 950
950
#08293E
oklch(26.9% 0.054 241.2)
#3399D9 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) | #7B9ADC | 0.066 |
| Deuteranopia (no green cones) | #648BD8 | 0.051 |
| Tritanopia (no blue cones) | #00A9AF | 0.090 |
| Achromatopsia (no color) | #919191 | 0.132 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3399D9
#3399D9
oklch(65.4% 0.132 241.1)
- #C97B2D
#C97B2D
oklch(65.3% 0.132 61.2)
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 #3399D9, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Sky Blue #448EE4 ΔE 0.038
- Chefchaouen Blue #4895EF ΔE 0.040
- Cornflower Blue #6495ED ΔE 0.053
- Water Blue #0E87CC ΔE 0.056
- Faded Blue #658CBB ΔE 0.059
- Cool Blue #4984B8 ΔE 0.067
- Soft Blue #6488EA ΔE 0.067
- Dodger Blue #1E90FF ΔE 0.067
Use #3399D9 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.