#309EDB
Closest named color: Chefchaouen Blue (#4895EF). oklch(66.6% 0.132 238.4), rgb(48, 158, 219).
Aa
Black text reads best on this color (7.03:1).
About this color
#309EDB is a medium-light, moderately saturated blue. In OKLCH its lightness is 67%, its chroma 0.132 and its hue 238°. Its hue sits on the cool side of the wheel. The nearest named color is Chefchaouen Blue (#4895EF), ΔE 0.045 away. Black text reads best on it, at 7.03:1.
| Hue family | Blues |
| Lightness | medium-light (67%) |
| Chroma | moderately saturated (0.132) |
| Temperature | cool |
| Nearest name | Chefchaouen Blue (#4895EF) |
| Black text | 7.03:1 |
| White text | 2.98:1 |
Values
| HEX | #309EDB |
| RGB | rgb(48, 158, 219) |
| HSL | hsl(201, 70%, 52%) |
| OKLCH | oklch(66.6% 0.132 238.4) |
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 #309EDB | 2.98:1 | Fails | Lc -61.4 | Content text, not long reading |
| Black text on #309EDB | 7.03:1 | AAA | Lc 48.0 | Large or bold text, headings |
| #309EDB text on white | 2.98:1 | Fails | Lc 56.0 | Large or bold text, headings |
| #309EDB text on black | 7.03:1 | AAA | Lc -45.7 | 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 500.
-
Step 50
50
#F0F6FB
oklch(97% 0.009 242.8)
-
Step 100
100
#DFECF5
oklch(93.6% 0.018 237.8)
-
Step 200
200
#C4DDEE
oklch(88.4% 0.036 237.6)
-
Step 300
300
#9AC7E6
oklch(80.8% 0.065 238.7)
-
Step 400
400
#5EAAD9
oklch(70.8% 0.102 237.7)
-
Step 500
500 (this color)
#309EDB
oklch(66.6% 0.132 238.4)
-
Step 600
600
#007CB3
oklch(55.7% 0.124 238.2)
-
Step 700
700
#006897
oklch(49.1% 0.109 238.1)
-
Step 800
800
#00557D
oklch(42.7% 0.096 238.5)
-
Step 900
900
#004769
oklch(37.8% 0.084 238.3)
-
Step 950
950
#062A3E
oklch(27.1% 0.054 238.2)
#309EDB 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) | #819EDE | 0.072 |
| Deuteranopia (no green cones) | #6A8EDA | 0.059 |
| Tritanopia (no blue cones) | #00ADB3 | 0.085 |
| Achromatopsia (no color) | #959595 | 0.132 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #309EDB
#309EDB
oklch(66.6% 0.132 238.4)
- #CF7D36
#CF7D36
oklch(66.5% 0.132 58.1)
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 #309EDB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Chefchaouen Blue #4895EF ΔE 0.045
- Dark Sky Blue #448EE4 ΔE 0.049
- Cornflower Blue #6495ED ΔE 0.056
- Faded Blue #658CBB ΔE 0.066
- Water Blue #0E87CC ΔE 0.069
- Turquoise Blue #06B1C4 ΔE 0.072
- Dodger Blue #1E90FF ΔE 0.073
- Soft Blue #6488EA ΔE 0.076
Use #309EDB 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.