#51BCDF
Closest named color: Vivid Sky Blue (#4CC9F0). oklch(74.7% 0.109 222.8), rgb(81, 188, 223).
Aa
Black text reads best on this color (9.60:1).
About this color
#51BCDF is a medium-light, moderately saturated teal or cyan. In OKLCH its lightness is 75%, its chroma 0.109 and its hue 223°. Its hue sits on the cool side of the wheel. The nearest named color is Vivid Sky Blue (#4CC9F0), ΔE 0.038 away. Black text reads best on it, at 9.60:1.
| Hue family | Teals and cyans |
| Lightness | medium-light (75%) |
| Chroma | moderately saturated (0.109) |
| Temperature | cool |
| Nearest name | Vivid Sky Blue (#4CC9F0) |
| Black text | 9.60:1 |
| White text | 2.18:1 |
Values
| HEX | #51BCDF |
| RGB | rgb(81, 188, 223) |
| HSL | hsl(195, 69%, 60%) |
| OKLCH | oklch(74.7% 0.109 222.8) |
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 #51BCDF | 2.18:1 | Fails | Lc -47.4 | Large or bold text, headings |
| Black text on #51BCDF | 9.60:1 | AAA | Lc 61.2 | Content text, not long reading |
| #51BCDF text on white | 2.18:1 | Fails | Lc 42.7 | Non-text elements, placeholder text |
| #51BCDF text on black | 9.60:1 | AAA | Lc -59.5 | 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
#EFF7FA
oklch(97.1% 0.009 222.1)
-
Step 100
100
#DCEDF4
oklch(93.6% 0.02 224.3)
-
Step 200
200
#BFDFEC
oklch(88.4% 0.038 224.3)
-
Step 300
300
#8FCBE1
oklch(80.9% 0.069 222.8)
-
Step 400
400 (this color)
#51BCDF
oklch(74.7% 0.109 222.8)
-
Step 500
500
#0098BD
oklch(63.1% 0.118 223.1)
-
Step 600
600
#00809F
oklch(55.6% 0.103 222.6)
-
Step 700
700
#006B86
oklch(49% 0.091 223.1)
-
Step 800
800
#00586E
oklch(42.7% 0.079 222.3)
-
Step 900
900
#00495C
oklch(37.6% 0.07 222.6)
-
Step 950
950
#002B38
oklch(26.8% 0.05 223.6)
#51BCDF 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) | #A8B8E1 | 0.088 |
| Deuteranopia (no green cones) | #94A9DF | 0.078 |
| Tritanopia (no blue cones) | #00C7C7 | 0.061 |
| Achromatopsia (no color) | #AFAFAF | 0.109 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #51BCDF
#51BCDF
oklch(74.7% 0.109 222.8)
- #E79674
#E79674
oklch(74.7% 0.109 43.5)
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 #51BCDF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Vivid Sky Blue #4CC9F0 ΔE 0.038
- Deep Sky Blue #00BFFF ΔE 0.049
- Bright Sky Blue #02CCFE ΔE 0.054
- Turquoise Blue #06B1C4 ΔE 0.059
- Lightblue #7BC8F6 ΔE 0.059
- Dark Turquoise #00CED1 ΔE 0.064
- Light Cornflower Blue #98C1D9 ΔE 0.070
- Sky #82CAFC ΔE 0.071
Use #51BCDF 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.