#259DD1
Closest named color: Dark Sky Blue (#448EE4). oklch(65.6% 0.126 233), rgb(37, 157, 209).
Aa
Black text reads best on this color (6.82:1).
About this color
#259DD1 is a medium-light, moderately saturated blue. In OKLCH its lightness is 66%, its chroma 0.126 and its hue 233°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Sky Blue (#448EE4), ΔE 0.057 away. Black text reads best on it, at 6.82:1.
| Hue family | Blues |
| Lightness | medium-light (66%) |
| Chroma | moderately saturated (0.126) |
| Temperature | cool |
| Nearest name | Dark Sky Blue (#448EE4) |
| Black text | 6.82:1 |
| White text | 3.07:1 |
Values
| HEX | #259DD1 |
| RGB | rgb(37, 157, 209) |
| HSL | hsl(198, 70%, 48%) |
| OKLCH | oklch(65.6% 0.126 233) |
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 #259DD1 | 3.07:1 | AA large text | Lc -62.6 | Content text, not long reading |
| Black text on #259DD1 | 6.82:1 | AA | Lc 46.8 | Large or bold text, headings |
| #259DD1 text on white | 3.07:1 | AA large text | Lc 57.2 | Large or bold text, headings |
| #259DD1 text on black | 6.82:1 | AA | Lc -44.5 | 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
#DFECF4
oklch(93.6% 0.018 234.5)
-
Step 200
200
#C4DEEC
oklch(88.6% 0.034 231.2)
-
Step 300
300
#99C8E2
oklch(80.8% 0.062 232.7)
-
Step 400
400
#5CABD4
oklch(70.7% 0.098 233.1)
-
Step 500
500 (this color)
#259DD1
oklch(65.6% 0.126 233)
-
Step 600
600
#007DAB
oklch(55.5% 0.115 233.2)
-
Step 700
700
#006991
oklch(49% 0.102 233.6)
-
Step 800
800
#005677
oklch(42.6% 0.088 233.1)
-
Step 900
900
#004864
oklch(37.8% 0.078 232.8)
-
Step 950
950
#042A3C
oklch(26.9% 0.053 234.4)
#259DD1 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) | #839CD3 | 0.080 |
| Deuteranopia (no green cones) | #6D8CD0 | 0.067 |
| Tritanopia (no blue cones) | #00ABAF | 0.075 |
| Achromatopsia (no color) | #939393 | 0.126 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #259DD1
#259DD1
oklch(65.6% 0.126 233)
- #CC7941
#CC7941
oklch(65.6% 0.126 52.7)
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 #259DD1, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Sky Blue #448EE4 ΔE 0.057
- Chefchaouen Blue #4895EF ΔE 0.059
- Faded Blue #658CBB ΔE 0.062
- Water Blue #0E87CC ΔE 0.064
- Turquoise Blue #06B1C4 ΔE 0.066
- Blue NCS #118AB2 ΔE 0.066
- Cornflower Blue #6495ED ΔE 0.070
- Cool Blue #4984B8 ΔE 0.071
Use #259DD1 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.