#21A5DB
Closest named color: Turquoise Blue (#06B1C4). oklch(68% 0.131 232.2), rgb(33, 165, 219).
Aa
Black text reads best on this color (7.46:1).
About this color
#21A5DB is a medium-light, moderately saturated blue. In OKLCH its lightness is 68%, its chroma 0.131 and its hue 232°. Its hue sits on the cool side of the wheel. The nearest named color is Turquoise Blue (#06B1C4), ΔE 0.056 away. Black text reads best on it, at 7.46:1.
| Hue family | Blues |
| Lightness | medium-light (68%) |
| Chroma | moderately saturated (0.131) |
| Temperature | cool |
| Nearest name | Turquoise Blue (#06B1C4) |
| Black text | 7.46:1 |
| White text | 2.81:1 |
Values
| HEX | #21A5DB |
| RGB | rgb(33, 165, 219) |
| HSL | hsl(197, 74%, 49%) |
| OKLCH | oklch(68% 0.131 232.2) |
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 #21A5DB | 2.81:1 | Fails | Lc -58.8 | Large or bold text, headings |
| Black text on #21A5DB | 7.46:1 | AAA | Lc 50.5 | Large or bold text, headings |
| #21A5DB text on white | 2.81:1 | Fails | Lc 53.6 | Large or bold text, headings |
| #21A5DB text on black | 7.46:1 | AAA | Lc -48.3 | 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 400.
-
Step 50
50
#EFF7FC
oklch(97.2% 0.011 234.8)
-
Step 100
100
#DBEDF7
oklch(93.6% 0.023 231.8)
-
Step 200
200
#BCDFF3
oklch(88.5% 0.046 233.1)
-
Step 300
300
#89CAED
oklch(80.8% 0.083 232.7)
-
Step 400
400 (this color)
#21A5DB
oklch(68% 0.131 232.2)
-
Step 500
500
#0096CA
oklch(63.2% 0.129 232.1)
-
Step 600
600
#007EAA
oklch(55.7% 0.113 231.8)
-
Step 700
700
#006A90
oklch(49.2% 0.1 232)
-
Step 800
800
#005676
oklch(42.6% 0.087 232.3)
-
Step 900
900
#004863
oklch(37.7% 0.077 231.8)
-
Step 950
950
#002B3D
oklch(27.1% 0.055 231.9)
#21A5DB 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) | #8AA3DE | 0.086 |
| Deuteranopia (no green cones) | #7293DA | 0.071 |
| Tritanopia (no blue cones) | #00B4B7 | 0.079 |
| Achromatopsia (no color) | #9A9A9A | 0.132 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #21A5DB
#21A5DB
oklch(68% 0.131 232.2)
- #D77F44
#D77F44
oklch(68.1% 0.132 52.5)
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 #21A5DB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Turquoise Blue #06B1C4 ΔE 0.056
- Chefchaouen Blue #4895EF ΔE 0.061
- Dark Sky Blue #448EE4 ΔE 0.068
- Cornflower Blue #6495ED ΔE 0.069
- Greyblue #77A1B5 ΔE 0.078
- Deep Sky Blue #00BFFF ΔE 0.079
- Faded Blue #658CBB ΔE 0.079
- Water Blue #0E87CC ΔE 0.085
Use #21A5DB 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.