#21AAA4
Closest named color: Light Sea Green (#20B2AA). oklch(66.9% 0.109 190.2), rgb(33, 170, 164).
Aa
Black text reads best on this color (7.35:1).
About this color
#21AAA4 is a medium-light, moderately saturated teal or cyan. In OKLCH its lightness is 67%, its chroma 0.109 and its hue 190°. Its hue sits on the cool side of the wheel. The nearest named color is Light Sea Green (#20B2AA), ΔE 0.023 away. Black text reads best on it, at 7.35:1.
| Hue family | Teals and cyans |
| Lightness | medium-light (67%) |
| Chroma | moderately saturated (0.109) |
| Temperature | cool |
| Nearest name | Light Sea Green (#20B2AA) |
| Black text | 7.35:1 |
| White text | 2.85:1 |
Values
| HEX | #21AAA4 |
| RGB | rgb(33, 170, 164) |
| HSL | hsl(177, 67%, 40%) |
| OKLCH | oklch(66.9% 0.109 190.2) |
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 #21AAA4 | 2.85:1 | Fails | Lc -59.5 | Large or bold text, headings |
| Black text on #21AAA4 | 7.35:1 | AAA | Lc 49.8 | Large or bold text, headings |
| #21AAA4 text on white | 2.85:1 | Fails | Lc 54.3 | Large or bold text, headings |
| #21AAA4 text on black | 7.35:1 | AAA | Lc -47.6 | 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
#EFF7F7
oklch(97% 0.008 197)
-
Step 100
100
#DCEEED
oklch(93.6% 0.019 192.8)
-
Step 200
200
#BEE2DF
oklch(88.6% 0.038 190.3)
-
Step 300
300
#8CCFCA
oklch(80.8% 0.068 190)
-
Step 400
400 (this color)
#21AAA4
oklch(66.9% 0.109 190.2)
-
Step 500
500
#009E98
oklch(63.1% 0.109 190)
-
Step 600
600
#008580
oklch(55.7% 0.096 190.1)
-
Step 700
700
#00706B
oklch(49.2% 0.085 189.4)
-
Step 800
800
#005C58
oklch(42.8% 0.074 189.6)
-
Step 900
900
#004C49
oklch(37.6% 0.065 190.2)
-
Step 950
950
#002E2C
oklch(27.2% 0.047 190.2)
#21AAA4 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) | #A0A1A4 | 0.116 |
| Deuteranopia (no green cones) | #8D93A5 | 0.108 |
| Tritanopia (no blue cones) | #00AFA8 | 0.014 |
| Achromatopsia (no color) | #999999 | 0.110 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #21AAA4
#21AAA4
oklch(66.9% 0.109 190.2)
- #CE7785
#CE7785
oklch(66.8% 0.11 10.1)
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 #21AAA4, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Light Sea Green #20B2AA ΔE 0.023
- Persian Green #2A9D8F ΔE 0.042
- Greeny Blue #42B395 ΔE 0.043
- Turquoise Blue #06B1C4 ΔE 0.046
- Cadet Blue #5F9EA0 ΔE 0.047
- Topaz #13BBAF ΔE 0.048
- Dull Teal #5F9E8F ΔE 0.048
- Sea #3C9992 ΔE 0.048
Use #21AAA4 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.