#21B8DF
Closest named color: Turquoise Blue (#06B1C4). oklch(72.7% 0.128 221.3), rgb(33, 184, 223).
Aa
Black text reads best on this color (8.98:1).
About this color
#21B8DF is a medium-light, moderately saturated teal or cyan. In OKLCH its lightness is 73%, its chroma 0.128 and its hue 221°. Its hue sits on the cool side of the wheel. The nearest named color is Turquoise Blue (#06B1C4), ΔE 0.042 away. Black text reads best on it, at 8.98:1.
| Hue family | Teals and cyans |
| Lightness | medium-light (73%) |
| Chroma | moderately saturated (0.128) |
| Temperature | cool |
| Nearest name | Turquoise Blue (#06B1C4) |
| Black text | 8.98:1 |
| White text | 2.33:1 |
Values
| HEX | #21B8DF |
| RGB | rgb(33, 184, 223) |
| HSL | hsl(192, 75%, 50%) |
| OKLCH | oklch(72.7% 0.128 221.3) |
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 #21B8DF | 2.33:1 | Fails | Lc -50.4 | Large or bold text, headings |
| Black text on #21B8DF | 8.98:1 | AAA | Lc 58.4 | Large or bold text, headings |
| #21B8DF text on white | 2.33:1 | Fails | Lc 45.6 | Large or bold text, headings |
| #21B8DF text on black | 8.98:1 | AAA | Lc -56.5 | 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
#EEF7FB
oklch(97.1% 0.011 226)
-
Step 100
100
#DAEEF5
oklch(93.6% 0.023 220.7)
-
Step 200
200
#BAE0EE
oklch(88.4% 0.044 222.2)
-
Step 300
300
#85CDE5
oklch(80.9% 0.079 221.1)
-
Step 400
400 (this color)
#21B8DF
oklch(72.7% 0.128 221.3)
-
Step 500
500
#0098BB
oklch(63% 0.116 221.8)
-
Step 600
600
#00809D
oklch(55.6% 0.102 221.1)
-
Step 700
700
#006C85
oklch(49.2% 0.09 221.2)
-
Step 800
800
#00586D
oklch(42.6% 0.078 221.3)
-
Step 900
900
#00495B
oklch(37.6% 0.069 221.4)
-
Step 950
950
#002C37
oklch(27.1% 0.049 219.4)
#21B8DF 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) | #A1B3E1 | 0.104 |
| Deuteranopia (no green cones) | #89A2DF | 0.092 |
| Tritanopia (no blue cones) | #00C4C5 | 0.059 |
| Achromatopsia (no color) | #A9A9A9 | 0.128 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #21B8DF
#21B8DF
oklch(72.7% 0.128 221.3)
- #E98A65
#E98A65
oklch(72.7% 0.127 41.8)
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 #21B8DF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Turquoise Blue #06B1C4 ΔE 0.042
- Deep Sky Blue #00BFFF ΔE 0.046
- Vivid Sky Blue #4CC9F0 ΔE 0.056
- Bright Sky Blue #02CCFE ΔE 0.062
- Dark Turquoise #00CED1 ΔE 0.072
- Topaz #13BBAF ΔE 0.076
- Light Sea Green #20B2AA ΔE 0.077
- Lightblue #7BC8F6 ΔE 0.084
Use #21B8DF 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.