#21C5D8
Closest named color: Dark Turquoise (#00CED1). oklch(75.5% 0.125 207.6), rgb(33, 197, 216).
Aa
Black text reads best on this color (10.04:1).
About this color
#21C5D8 is a medium-light, moderately saturated teal or cyan. In OKLCH its lightness is 75%, its chroma 0.125 and its hue 208°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Turquoise (#00CED1), ΔE 0.030 away. Black text reads best on it, at 10.04:1.
| Hue family | Teals and cyans |
| Lightness | medium-light (75%) |
| Chroma | moderately saturated (0.125) |
| Temperature | cool |
| Nearest name | Dark Turquoise (#00CED1) |
| Black text | 10.04:1 |
| White text | 2.09:1 |
Values
| HEX | #21C5D8 |
| RGB | rgb(33, 197, 216) |
| HSL | hsl(186, 73%, 49%) |
| OKLCH | oklch(75.5% 0.125 207.6) |
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 #21C5D8 | 2.09:1 | Fails | Lc -44.9 | Non-text elements, placeholder text |
| Black text on #21C5D8 | 10.04:1 | AAA | Lc 63.6 | Content text, not long reading |
| #21C5D8 text on white | 2.09:1 | Fails | Lc 40.4 | Non-text elements, placeholder text |
| #21C5D8 text on black | 10.04:1 | AAA | Lc -61.9 | Content text, not long reading |
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
#EEF8F9
oklch(97.2% 0.011 204.1)
-
Step 100
100
#DAEEF2
oklch(93.6% 0.022 211)
-
Step 200
200
#B9E2E8
oklch(88.6% 0.043 207.3)
-
Step 300
300
#82CFDB
oklch(80.9% 0.078 208.3)
-
Step 400
400 (this color)
#21C5D8
oklch(75.5% 0.125 207.6)
-
Step 500
500
#009BAB
oklch(63% 0.108 207.7)
-
Step 600
600
#008290
oklch(55.5% 0.095 208)
-
Step 700
700
#006E79
oklch(49.2% 0.084 206.9)
-
Step 800
800
#005A64
oklch(42.8% 0.073 207.9)
-
Step 900
900
#004B53
oklch(37.7% 0.065 207)
-
Step 950
950
#002D32
oklch(27.1% 0.046 206.3)
#21C5D8 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) | #B3BDD9 | 0.120 |
| Deuteranopia (no green cones) | #9BACD8 | 0.109 |
| Tritanopia (no blue cones) | #00CECB | 0.037 |
| Achromatopsia (no color) | #B3B3B3 | 0.125 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #21C5D8
#21C5D8
oklch(75.5% 0.125 207.6)
- #F48F83
#F48F83
oklch(75.4% 0.125 27.6)
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 #21C5D8, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Turquoise #00CED1 ΔE 0.030
- Vivid Sky Blue #4CC9F0 ΔE 0.042
- Medium Turquoise #48D1CC ΔE 0.047
- Aqua Blue #02D8E9 ΔE 0.052
- Bright Sky Blue #02CCFE ΔE 0.054
- Turquoise Blue #06B1C4 ΔE 0.059
- Topaz #13BBAF ΔE 0.061
- Deep Sky Blue #00BFFF ΔE 0.064
Use #21C5D8 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.