#51ABFD
Closest named color: Deep Sky Blue (#00BFFF). oklch(72.2% 0.148 248.7), rgb(81, 171, 253).
Aa
Black text reads best on this color (8.59:1).
About this color
#51ABFD is a medium-light, vivid blue. In OKLCH its lightness is 72%, its chroma 0.148 and its hue 249°. Its hue sits on the cool side of the wheel. The nearest named color is Deep Sky Blue (#00BFFF), ΔE 0.056 away. Black text reads best on it, at 8.59:1.
| Hue family | Blues |
| Lightness | medium-light (72%) |
| Chroma | vivid (0.148) |
| Temperature | cool |
| Nearest name | Deep Sky Blue (#00BFFF) |
| Black text | 8.59:1 |
| White text | 2.44:1 |
Values
| HEX | #51ABFD |
| RGB | rgb(81, 171, 253) |
| HSL | hsl(209, 98%, 65%) |
| OKLCH | oklch(72.2% 0.148 248.7) |
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 #51ABFD | 2.44:1 | Fails | Lc -52.8 | Large or bold text, headings |
| Black text on #51ABFD | 8.59:1 | AAA | Lc 56.2 | Large or bold text, headings |
| #51ABFD text on white | 2.44:1 | Fails | Lc 47.8 | Large or bold text, headings |
| #51ABFD text on black | 8.59:1 | AAA | Lc -54.2 | 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
#EFF6FE
oklch(97% 0.013 251.6)
-
Step 100
100
#DDECFB
oklch(93.6% 0.026 248.1)
-
Step 200
200
#C0DDFA
oklch(88.6% 0.051 248.4)
-
Step 300
300
#91C6FA
oklch(80.9% 0.092 248.6)
-
Step 400
400 (this color)
#51ABFD
oklch(72.2% 0.148 248.7)
-
Step 500
500
#008DEC
oklch(63.1% 0.173 248.9)
-
Step 600
600
#0077C7
oklch(55.7% 0.152 248.5)
-
Step 700
700
#0063A9
oklch(49% 0.136 249.1)
-
Step 800
800
#00518B
oklch(42.6% 0.117 248.8)
-
Step 900
900
#004475
oklch(37.8% 0.103 248.3)
-
Step 950
950
#002848
oklch(27% 0.073 248.1)
#51ABFD 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) | #86AFFF | 0.053 |
| Deuteranopia (no green cones) | #6E9EFB | 0.039 |
| Tritanopia (no blue cones) | #00BEC8 | 0.111 |
| Achromatopsia (no color) | #A6A6A6 | 0.148 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #51ABFD
#51ABFD
oklch(72.2% 0.148 248.7)
- #E09224
#E09224
oklch(72.3% 0.147 69.1)
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 #51ABFD, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Deep Sky Blue #00BFFF ΔE 0.056
- Cornflower Blue #6495ED ΔE 0.058
- Chefchaouen Blue #4895EF ΔE 0.061
- Carolina Blue #8AB8FE ΔE 0.069
- Periwinkle Blue #8F99FB ΔE 0.073
- Dark Sky Blue #448EE4 ΔE 0.083
- Dodger Blue #1E90FF ΔE 0.083
- Bright Sky Blue #02CCFE ΔE 0.089
Use #51ABFD 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.