#309BDB
Closest named color: Chefchaouen Blue (#4895EF). oklch(65.9% 0.134 240.3), rgb(48, 155, 219).
Aa
Black text reads best on this color (6.83:1).
About this color
#309BDB is a medium-light, moderately saturated blue. In OKLCH its lightness is 66%, its chroma 0.134 and its hue 240°. Its hue sits on the cool side of the wheel. The nearest named color is Chefchaouen Blue (#4895EF), ΔE 0.041 away. Black text reads best on it, at 6.83:1.
| Hue family | Blues |
| Lightness | medium-light (66%) |
| Chroma | moderately saturated (0.134) |
| Temperature | cool |
| Nearest name | Chefchaouen Blue (#4895EF) |
| Black text | 6.83:1 |
| White text | 3.07:1 |
Values
| HEX | #309BDB |
| RGB | rgb(48, 155, 219) |
| HSL | hsl(202, 70%, 52%) |
| OKLCH | oklch(65.9% 0.134 240.3) |
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 #309BDB | 3.07:1 | AA large text | Lc -62.6 | Content text, not long reading |
| Black text on #309BDB | 6.83:1 | AA | Lc 46.9 | Large or bold text, headings |
| #309BDB text on white | 3.07:1 | AA large text | Lc 57.2 | Large or bold text, headings |
| #309BDB text on black | 6.83:1 | AA | Lc -44.6 | 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
#C4DDEF
oklch(88.5% 0.036 239.2)
-
Step 300
300
#9BC7E7
oklch(80.9% 0.065 240.2)
-
Step 400
400
#5FA9DB
oklch(70.7% 0.104 240)
-
Step 500
500 (this color)
#309BDB
oklch(65.9% 0.134 240.3)
-
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
#06293F
oklch(26.9% 0.056 241.4)
#309BDB 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) | #7D9CDE | 0.069 |
| Deuteranopia (no green cones) | #658CDA | 0.054 |
| Tritanopia (no blue cones) | #00ABB1 | 0.090 |
| Achromatopsia (no color) | #939393 | 0.134 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #309BDB
#309BDB
oklch(65.9% 0.134 240.3)
- #CC7C2E
#CC7C2E
oklch(65.9% 0.134 60.5)
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 #309BDB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Chefchaouen Blue #4895EF ΔE 0.041
- Dark Sky Blue #448EE4 ΔE 0.041
- Cornflower Blue #6495ED ΔE 0.053
- Water Blue #0E87CC ΔE 0.061
- Faded Blue #658CBB ΔE 0.063
- Dodger Blue #1E90FF ΔE 0.067
- Soft Blue #6488EA ΔE 0.070
- Cool Blue #4984B8 ΔE 0.072
Use #309BDB 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.