#51D4E5
Closest named color: Aqua Blue (#02D8E9). oklch(80.5% 0.115 207.2), rgb(81, 212, 229).
Aa
Black text reads best on this color (11.89:1).
About this color
#51D4E5 is a light, moderately saturated teal or cyan. In OKLCH its lightness is 81%, its chroma 0.115 and its hue 207°. Its hue sits on the cool side of the wheel. The nearest named color is Aqua Blue (#02D8E9), ΔE 0.023 away. Black text reads best on it, at 11.89:1.
| Hue family | Teals and cyans |
| Lightness | light (81%) |
| Chroma | moderately saturated (0.115) |
| Temperature | cool |
| Nearest name | Aqua Blue (#02D8E9) |
| Black text | 11.89:1 |
| White text | 1.76:1 |
Values
| HEX | #51D4E5 |
| RGB | rgb(81, 212, 229) |
| HSL | hsl(187, 74%, 61%) |
| OKLCH | oklch(80.5% 0.115 207.2) |
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 #51D4E5 | 1.76:1 | Fails | Lc -36.0 | Non-text elements, placeholder text |
| Black text on #51D4E5 | 11.89:1 | AAA | Lc 71.8 | Content text, not long reading |
| #51D4E5 text on white | 1.76:1 | Fails | Lc 32.0 | Non-text elements, placeholder text |
| #51D4E5 text on black | 11.89:1 | AAA | Lc -70.6 | 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 300.
-
Step 50
50
#EAF9FB
oklch(97.2% 0.016 206.4)
-
Step 100
100
#D1F1F5
oklch(93.6% 0.034 205.8)
-
Step 200
200
#A7E6EF
oklch(88.6% 0.065 207.1)
-
Step 300
300 (this color)
#51D4E5
oklch(80.5% 0.115 207.2)
-
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)
#51D4E5 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) | #C3CCE6 | 0.111 |
| Deuteranopia (no green cones) | #ADBCE5 | 0.102 |
| Tritanopia (no blue cones) | #00DDD9 | 0.041 |
| Achromatopsia (no color) | #C3C3C3 | 0.116 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #51D4E5
#51D4E5
oklch(80.5% 0.115 207.2)
- #FFA398
#FFA398
oklch(80.5% 0.111 27.2)
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 #51D4E5, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Aqua Blue #02D8E9 ΔE 0.023
- Medium Turquoise #48D1CC ΔE 0.036
- Vivid Sky Blue #4CC9F0 ΔE 0.039
- Dark Turquoise #00CED1 ΔE 0.043
- Sky Blue #87CEEB ΔE 0.046
- Turquoise #40E0D0 ΔE 0.053
- Bright Sky Blue #02CCFE ΔE 0.053
- Lightblue #7BC8F6 ΔE 0.056
Use #51D4E5 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.