#51DEF0
Closest named color: Aqua Blue (#02D8E9). oklch(83.2% 0.121 207.2), rgb(81, 222, 240).
Aa
Black text reads best on this color (13.05:1).
About this color
#51DEF0 is a light, moderately saturated teal or cyan. In OKLCH its lightness is 83%, its chroma 0.121 and its hue 207°. Its hue sits on the cool side of the wheel. The nearest named color is Aqua Blue (#02D8E9), ΔE 0.032 away. Black text reads best on it, at 13.05:1.
| Hue family | Teals and cyans |
| Lightness | light (83%) |
| Chroma | moderately saturated (0.121) |
| Temperature | cool |
| Nearest name | Aqua Blue (#02D8E9) |
| Black text | 13.05:1 |
| White text | 1.60:1 |
Values
| HEX | #51DEF0 |
| RGB | rgb(81, 222, 240) |
| HSL | hsl(187, 84%, 63%) |
| OKLCH | oklch(83.2% 0.121 207.2) |
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 #51DEF0 | 1.60:1 | Fails | Lc -30.5 | Non-text elements, placeholder text |
| Black text on #51DEF0 | 13.05:1 | AAA | Lc 76.8 | Fine for body text |
| #51DEF0 text on white | 1.60:1 | Fails | Lc 27.0 | Dividers and decoration only |
| #51DEF0 text on black | 13.05:1 | AAA | Lc -76.0 | Fine for body text |
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 300.
-
Step 50
50
#EAF9FB
oklch(97.2% 0.016 206.4)
-
Step 100
100
#D0F1F6
oklch(93.6% 0.035 207.7)
-
Step 200
200
#A4E6F0
oklch(88.4% 0.067 207.8)
-
Step 300
300 (this color)
#51DEF0
oklch(83.2% 0.121 207.2)
-
Step 400
400
#00B5C7
oklch(70.7% 0.121 207.4)
-
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
#005A63
oklch(42.7% 0.073 206.6)
-
Step 900
900
#004B53
oklch(37.7% 0.065 207)
-
Step 950
950
#002D32
oklch(27.1% 0.046 206.3)
#51DEF0 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) | #CCD6F1 | 0.117 |
| Deuteranopia (no green cones) | #B5C5F0 | 0.107 |
| Tritanopia (no blue cones) | #00E7E3 | 0.041 |
| Achromatopsia (no color) | #CCCCCC | 0.122 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #51DEF0
#51DEF0
oklch(83.2% 0.121 207.2)
- #FFB1A7
#FFB1A7
oklch(83.2% 0.093 27.3)
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 #51DEF0, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Aqua Blue #02D8E9 ΔE 0.032
- Robin's Egg #6DEDFD ΔE 0.048
- Turquoise #40E0D0 ΔE 0.050
- Sky Blue #87CEEB ΔE 0.054
- Medium Turquoise #48D1CC ΔE 0.056
- Vivid Sky Blue #4CC9F0 ΔE 0.059
- Light Sky Blue #87CEFA ΔE 0.062
- Bright Light Blue #26F7FD ΔE 0.065
Use #51DEF0 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.