#21B290
Closest named color: Greeny Blue (#42B395). oklch(68.3% 0.126 171.8), rgb(33, 178, 144).
Aa
Black text reads best on this color (7.83:1).
About this color
#21B290 is a medium-light, moderately saturated teal or cyan. In OKLCH its lightness is 68%, its chroma 0.126 and its hue 172°. Its hue sits on the cool side of the wheel. The nearest named color is Greeny Blue (#42B395), ΔE 0.018 away. Black text reads best on it, at 7.83:1.
| Hue family | Teals and cyans |
| Lightness | medium-light (68%) |
| Chroma | moderately saturated (0.126) |
| Temperature | cool |
| Nearest name | Greeny Blue (#42B395) |
| Black text | 7.83:1 |
| White text | 2.68:1 |
Values
| HEX | #21B290 |
| RGB | rgb(33, 178, 144) |
| HSL | hsl(166, 69%, 41%) |
| OKLCH | oklch(68.3% 0.126 171.8) |
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 #21B290 | 2.68:1 | Fails | Lc -56.8 | Large or bold text, headings |
| Black text on #21B290 | 7.83:1 | AAA | Lc 52.4 | Large or bold text, headings |
| #21B290 text on white | 2.68:1 | Fails | Lc 51.6 | Large or bold text, headings |
| #21B290 text on black | 7.83:1 | AAA | Lc -50.3 | 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
#EFF8F4
oklch(97.1% 0.011 167.8)
-
Step 100
100
#DCEFE8
oklch(93.6% 0.022 171.8)
-
Step 200
200
#BDE3D6
oklch(88.5% 0.044 172.5)
-
Step 300
300
#8BD2BB
oklch(81% 0.079 171.9)
-
Step 400
400 (this color)
#21B290
oklch(68.3% 0.126 171.8)
-
Step 500
500
#00A181
oklch(63.2% 0.122 172)
-
Step 600
600
#00876C
oklch(55.5% 0.108 172.1)
-
Step 700
700
#00725A
oklch(49.2% 0.096 171.5)
-
Step 800
800
#005D49
oklch(42.6% 0.083 171.6)
-
Step 900
900
#004E3D
oklch(37.8% 0.073 171.8)
-
Step 950
950
#002E23
oklch(26.8% 0.052 171.9)
#21B290 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) | #ACA68E | 0.129 |
| Deuteranopia (no green cones) | #9A9992 | 0.123 |
| Tritanopia (no blue cones) | #00B4A8 | 0.033 |
| Achromatopsia (no color) | #9E9E9E | 0.127 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #21B290
#21B290
oklch(68.3% 0.126 171.8)
- #D477A2
#D477A2
oklch(68.4% 0.126 351.8)
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 #21B290, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Greeny Blue #42B395 ΔE 0.018
- Bluey Green #2BB179 ΔE 0.031
- Dark Seafoam Green #3EAF76 ΔE 0.034
- Dark Seafoam #1FB57A ΔE 0.035
- Light Sea Green #20B2AA ΔE 0.039
- Green Teal #0CB577 ΔE 0.040
- Green Blue #01C08D ΔE 0.043
- Medium Sea Green #3CB371 ΔE 0.043
Use #21B290 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.