#51C4B5
Closest named color: Medium Aquamarine (#66CDAA). oklch(75.1% 0.106 183.5), rgb(81, 196, 181).
Aa
Black text reads best on this color (9.91:1).
About this color
#51C4B5 is a medium-light, moderately saturated teal or cyan. In OKLCH its lightness is 75%, its chroma 0.106 and its hue 184°. Its hue sits on the cool side of the wheel. The nearest named color is Medium Aquamarine (#66CDAA), ΔE 0.038 away. Black text reads best on it, at 9.91:1.
| Hue family | Teals and cyans |
| Lightness | medium-light (75%) |
| Chroma | moderately saturated (0.106) |
| Temperature | cool |
| Nearest name | Medium Aquamarine (#66CDAA) |
| Black text | 9.91:1 |
| White text | 2.11:1 |
Values
| HEX | #51C4B5 |
| RGB | rgb(81, 196, 181) |
| HSL | hsl(172, 49%, 54%) |
| OKLCH | oklch(75.1% 0.106 183.5) |
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 #51C4B5 | 2.11:1 | Fails | Lc -45.9 | Large or bold text, headings |
| Black text on #51C4B5 | 9.91:1 | AAA | Lc 62.7 | Content text, not long reading |
| #51C4B5 text on white | 2.11:1 | Fails | Lc 41.2 | Non-text elements, placeholder text |
| #51C4B5 text on black | 9.91:1 | AAA | Lc -61.0 | 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
#EFF7F6
oklch(97% 0.009 188.1)
-
Step 100
100
#DDEEEB
oklch(93.6% 0.018 184.3)
-
Step 200
200
#BFE2DB
oklch(88.6% 0.038 182)
-
Step 300
300
#90CFC5
oklch(80.9% 0.066 183.7)
-
Step 400
400 (this color)
#51C4B5
oklch(75.1% 0.106 183.5)
-
Step 500
500
#009F90
oklch(63.1% 0.112 183.2)
-
Step 600
600
#008679
oklch(55.7% 0.099 183.1)
-
Step 700
700
#007066
oklch(49% 0.087 184.2)
-
Step 800
800
#005C53
oklch(42.6% 0.076 183.4)
-
Step 900
900
#004D45
oklch(37.7% 0.067 183.1)
-
Step 950
950
#002E29
oklch(27.1% 0.048 183.6)
#51C4B5 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) | #BBBAB4 | 0.112 |
| Deuteranopia (no green cones) | #AAADB6 | 0.106 |
| Tritanopia (no blue cones) | #00C8BF | 0.027 |
| Achromatopsia (no color) | #B2B2B2 | 0.107 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #51C4B5
#51C4B5
oklch(75.1% 0.106 183.5)
- #E791A7
#E791A7
oklch(75.1% 0.107 3.4)
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 #51C4B5, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Medium Aquamarine #66CDAA ΔE 0.038
- Topaz #13BBAF ΔE 0.040
- Medium Turquoise #48D1CC ΔE 0.041
- Dark Turquoise #00CED1 ΔE 0.043
- Pale Teal #82CBB2 ΔE 0.048
- Seafoam Blue #78D1B6 ΔE 0.052
- Greeny Blue #42B395 ΔE 0.060
- Light Sea Green #20B2AA ΔE 0.061
Use #51C4B5 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.