#309ADA
Closest named color: Dark Sky Blue (#448EE4). oklch(65.6% 0.133 240.5), rgb(48, 154, 218).
Aa
Black text reads best on this color (6.76:1).
About this color
#309ADA is a medium-light, moderately saturated blue. In OKLCH its lightness is 66%, its chroma 0.133 and its hue 240°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Sky Blue (#448EE4), ΔE 0.040 away. Black text reads best on it, at 6.76:1.
| Hue family | Blues |
| Lightness | medium-light (66%) |
| Chroma | moderately saturated (0.133) |
| Temperature | cool |
| Nearest name | Dark Sky Blue (#448EE4) |
| Black text | 6.76:1 |
| White text | 3.10:1 |
Values
| HEX | #309ADA |
| RGB | rgb(48, 154, 218) |
| HSL | hsl(203, 70%, 52%) |
| OKLCH | oklch(65.6% 0.133 240.5) |
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 #309ADA | 3.10:1 | AA large text | Lc -63.0 | Content text, not long reading |
| Black text on #309ADA | 6.76:1 | AA | Lc 46.4 | Large or bold text, headings |
| #309ADA text on white | 3.10:1 | AA large text | Lc 57.6 | Large or bold text, headings |
| #309ADA text on black | 6.76:1 | AA | Lc -44.1 | 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
#F0F6FB
oklch(97% 0.009 242.8)
-
Step 100
100
#DFECF6
oklch(93.6% 0.019 240.7)
-
Step 200
200
#C5DDEF
oklch(88.5% 0.036 240.3)
-
Step 300
300
#9BC7E7
oklch(80.9% 0.065 240.2)
-
Step 400
400
#60A9DB
oklch(70.7% 0.104 240.3)
-
Step 500
500 (this color)
#309ADA
oklch(65.6% 0.133 240.5)
-
Step 600
600
#007BB6
oklch(55.6% 0.128 240.2)
-
Step 700
700
#00679A
oklch(49.1% 0.113 240.5)
-
Step 800
800
#00547F
oklch(42.6% 0.099 240.7)
-
Step 900
900
#00466B
oklch(37.7% 0.087 240.8)
-
Step 950
950
#07293F
oklch(26.9% 0.056 241.9)
#309ADA 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) | #7C9BDD | 0.068 |
| Deuteranopia (no green cones) | #658BD9 | 0.054 |
| Tritanopia (no blue cones) | #00AAB0 | 0.090 |
| Achromatopsia (no color) | #929292 | 0.133 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #309ADA
#309ADA
oklch(65.6% 0.133 240.5)
- #CB7B2D
#CB7B2D
oklch(65.6% 0.134 60.4)
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 #309ADA, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Sky Blue #448EE4 ΔE 0.040
- Chefchaouen Blue #4895EF ΔE 0.041
- Cornflower Blue #6495ED ΔE 0.054
- Water Blue #0E87CC ΔE 0.058
- Faded Blue #658CBB ΔE 0.061
- Dodger Blue #1E90FF ΔE 0.067
- Soft Blue #6488EA ΔE 0.069
- Cool Blue #4984B8 ΔE 0.070
Use #309ADA 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.