#21B2D4
Closest named color: Turquoise Blue (#06B1C4). oklch(70.7% 0.122 219), rgb(33, 178, 212).
Aa
Black text reads best on this color (8.38:1).
About this color
#21B2D4 is a medium-light, moderately saturated teal or cyan. In OKLCH its lightness is 71%, its chroma 0.122 and its hue 219°. Its hue sits on the cool side of the wheel. The nearest named color is Turquoise Blue (#06B1C4), ΔE 0.025 away. Black text reads best on it, at 8.38:1.
| Hue family | Teals and cyans |
| Lightness | medium-light (71%) |
| Chroma | moderately saturated (0.122) |
| Temperature | cool |
| Nearest name | Turquoise Blue (#06B1C4) |
| Black text | 8.38:1 |
| White text | 2.50:1 |
Values
| HEX | #21B2D4 |
| RGB | rgb(33, 178, 212) |
| HSL | hsl(191, 73%, 48%) |
| OKLCH | oklch(70.7% 0.122 219) |
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 #21B2D4 | 2.50:1 | Fails | Lc -53.7 | Large or bold text, headings |
| Black text on #21B2D4 | 8.38:1 | AAA | Lc 55.3 | Large or bold text, headings |
| #21B2D4 text on white | 2.50:1 | Fails | Lc 48.7 | Large or bold text, headings |
| #21B2D4 text on black | 8.38:1 | AAA | Lc -53.3 | 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
#EEF7FA
oklch(97% 0.01 219.6)
-
Step 100
100
#DBEEF4
oklch(93.7% 0.022 218.6)
-
Step 200
200
#BBE0EC
oklch(88.4% 0.042 219.4)
-
Step 300
300
#87CDE2
oklch(80.9% 0.076 218.8)
-
Step 400
400 (this color)
#21B2D4
oklch(70.7% 0.122 219)
-
Step 500
500
#0099B8
oklch(63.1% 0.114 219)
-
Step 600
600
#00819B
oklch(55.7% 0.1 218.5)
-
Step 700
700
#006C83
oklch(49.1% 0.089 219.3)
-
Step 800
800
#00586C
oklch(42.6% 0.078 220.2)
-
Step 900
900
#004A5A
oklch(37.8% 0.068 218.5)
-
Step 950
950
#002C37
oklch(27.1% 0.049 219.4)
#21B2D4 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) | #9DADD6 | 0.103 |
| Deuteranopia (no green cones) | #869DD4 | 0.091 |
| Tritanopia (no blue cones) | #00BDBD | 0.054 |
| Achromatopsia (no color) | #A4A4A4 | 0.122 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #21B2D4
#21B2D4
oklch(70.7% 0.122 219)
- #E18566
#E18566
oklch(70.8% 0.122 39.3)
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 #21B2D4, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Turquoise Blue #06B1C4 ΔE 0.025
- Light Sea Green #20B2AA ΔE 0.064
- Deep Sky Blue #00BFFF ΔE 0.065
- Topaz #13BBAF ΔE 0.069
- Greyblue #77A1B5 ΔE 0.073
- Vivid Sky Blue #4CC9F0 ΔE 0.075
- Dark Turquoise #00CED1 ΔE 0.082
- Cadet Blue #5F9EA0 ΔE 0.082
Use #21B2D4 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.