#21ADFD
Closest named color: Deep Sky Blue (#00BFFF). oklch(71.6% 0.16 241.4), rgb(33, 173, 253).
Aa
Black text reads best on this color (8.46:1).
About this color
#21ADFD is a medium-light, vivid blue. In OKLCH its lightness is 72%, its chroma 0.160 and its hue 241°. Its hue sits on the cool side of the wheel. The nearest named color is Deep Sky Blue (#00BFFF), ΔE 0.048 away. Black text reads best on it, at 8.46:1.
| Hue family | Blues |
| Lightness | medium-light (72%) |
| Chroma | vivid (0.160) |
| Temperature | cool |
| Nearest name | Deep Sky Blue (#00BFFF) |
| Black text | 8.46:1 |
| White text | 2.48:1 |
Values
| HEX | #21ADFD |
| RGB | rgb(33, 173, 253) |
| HSL | hsl(202, 98%, 56%) |
| OKLCH | oklch(71.6% 0.16 241.4) |
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 #21ADFD | 2.48:1 | Fails | Lc -53.2 | Large or bold text, headings |
| Black text on #21ADFD | 8.46:1 | AAA | Lc 55.8 | Large or bold text, headings |
| #21ADFD text on white | 2.48:1 | Fails | Lc 48.2 | Large or bold text, headings |
| #21ADFD text on black | 8.46:1 | AAA | Lc -53.8 | 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
#EEF7FE
oklch(97.1% 0.013 241)
-
Step 100
100
#DAEDFC
oklch(93.7% 0.029 241.6)
-
Step 200
200
#BADFFB
oklch(88.6% 0.055 240.9)
-
Step 300
300
#84C9FB
oklch(80.9% 0.1 241)
-
Step 400
400 (this color)
#21ADFD
oklch(71.6% 0.16 241.4)
-
Step 500
500
#0092DA
oklch(63.1% 0.148 241.4)
-
Step 600
600
#007AB8
oklch(55.5% 0.131 241.7)
-
Step 700
700
#00679B
oklch(49.1% 0.115 241)
-
Step 800
800
#005480
oklch(42.6% 0.1 241.3)
-
Step 900
900
#00466C
oklch(37.7% 0.089 241.5)
-
Step 950
950
#002942
oklch(26.9% 0.063 241.6)
#21ADFD 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) | #87AFFF | 0.077 |
| Deuteranopia (no green cones) | #699CFC | 0.058 |
| Tritanopia (no blue cones) | #00C1CA | 0.106 |
| Achromatopsia (no color) | #A4A4A4 | 0.160 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #21ADFD
#21ADFD
oklch(71.6% 0.16 241.4)
- #E98818
#E98818
oklch(71.6% 0.16 61.3)
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 #21ADFD, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Deep Sky Blue #00BFFF ΔE 0.048
- Chefchaouen Blue #4895EF ΔE 0.063
- Cornflower Blue #6495ED ΔE 0.069
- Dodger Blue #1E90FF ΔE 0.079
- Dark Sky Blue #448EE4 ΔE 0.083
- Bright Sky Blue #02CCFE ΔE 0.085
- Carolina Blue #8AB8FE ΔE 0.088
- Vivid Sky Blue #4CC9F0 ΔE 0.090
Use #21ADFD 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.