#51DBFF
Closest named color: Aqua Blue (#02D8E9). oklch(83.1% 0.127 218.7), rgb(81, 219, 255).
Aa
Black text reads best on this color (12.92:1).
About this color
#51DBFF is a light, moderately saturated teal or cyan. In OKLCH its lightness is 83%, its chroma 0.127 and its hue 219°. Its hue sits on the cool side of the wheel. The nearest named color is Aqua Blue (#02D8E9), ΔE 0.042 away. Black text reads best on it, at 12.92:1.
| Hue family | Teals and cyans |
| Lightness | light (83%) |
| Chroma | moderately saturated (0.127) |
| Temperature | cool |
| Nearest name | Aqua Blue (#02D8E9) |
| Black text | 12.92:1 |
| White text | 1.62:1 |
Values
| HEX | #51DBFF |
| RGB | rgb(81, 219, 255) |
| HSL | hsl(192, 100%, 66%) |
| OKLCH | oklch(83.1% 0.127 218.7) |
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 #51DBFF | 1.62:1 | Fails | Lc -31.1 | Non-text elements, placeholder text |
| Black text on #51DBFF | 12.92:1 | AAA | Lc 76.2 | Fine for body text |
| #51DBFF text on white | 1.62:1 | Fails | Lc 27.6 | Dividers and decoration only |
| #51DBFF text on black | 12.92:1 | AAA | Lc -75.4 | 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
#EAF9FD
oklch(97.2% 0.017 215.5)
-
Step 100
100
#D0F0FB
oklch(93.5% 0.037 220.5)
-
Step 200
200
#A4E5F9
oklch(88.5% 0.071 218.9)
-
Step 300
300 (this color)
#51DBFF
oklch(83.1% 0.127 218.7)
-
Step 400
400
#00B3D6
oklch(70.8% 0.128 218.5)
-
Step 500
500
#0099B8
oklch(63.1% 0.114 219)
-
Step 600
600
#00819B
oklch(55.7% 0.1 218.5)
-
Step 700
700
#006C82
oklch(49.1% 0.088 218.4)
-
Step 800
800
#00596B
oklch(42.8% 0.077 217.7)
-
Step 900
900
#004A5A
oklch(37.8% 0.068 218.5)
-
Step 950
950
#002C36
oklch(27% 0.048 217.4)
#51DBFF 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) | #C4D5FF | 0.107 |
| Deuteranopia (no green cones) | #ACC3FF | 0.097 |
| Tritanopia (no blue cones) | #00E7E6 | 0.060 |
| Achromatopsia (no color) | #CBCBCB | 0.127 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #51DBFF
#51DBFF
oklch(83.1% 0.127 218.7)
- #FFB299
#FFB299
oklch(83.1% 0.097 38.7)
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 #51DBFF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Aqua Blue #02D8E9 ΔE 0.042
- Light Sky Blue #87CEFA ΔE 0.048
- Sky Blue #87CEEB ΔE 0.049
- Vivid Sky Blue #4CC9F0 ΔE 0.050
- Bright Sky Blue #02CCFE ΔE 0.052
- Lightblue #7BC8F6 ΔE 0.053
- Sky #82CAFC ΔE 0.053
- Robin's Egg #6DEDFD ΔE 0.056
Use #51DBFF 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.