Activewear Size Calculator: Leggings to Tops
This activewear size calculator lets you pick fit mode — compression (Lululemon, Alo) or relaxed (Outdoor Voices, Vuori). Enter chest, waist, hip and the tool returns the right size for leggings, sports tops, and shorts in your chosen fit. Works across compression-heavy and lifestyle-athleisure brands. Use the calculator below to get your exact fit in 30 seconds.
How it works
Measure yourself
Take your bust, waist, and hips with a soft tape. See the full measurement guide.
Enter the numbers
Type your measurements into the calculator above. Pick inches or cm — the tool converts both ways.
Get your size
Match the result against the brand's chart and order with confidence.
Women's tops & dresses — bust-driven sizing
| Size | US | UK | EU | Bust |
|---|---|---|---|---|
| XS | 0–2 | 4–6 | 32–34 | 31–33" |
| S | 4–6 | 8–10 | 36–38 | 33–35" |
| M | 8–10 | 12–14 | 40–42 | 35–37" |
| L | 12–14 | 16–18 | 44–46 | 38–40" |
| XL | 16–18 | 20–22 | 48–50 | 41–43" |
| XXL | 20–22 | 24–26 | 52–54 | 44–46" |
Frequently Asked Questions
Should I size up for compression activewear?
No — match the calculator's compression-mode number. Sizing up defeats the support; sizing down causes pinching at the waistband.
How do leggings sizes compare to jeans?
Leggings run 0.5–1 size smaller than jeans because of stretch. A US 8 in jeans is often a M (US 6) in leggings.
What's the difference between high-rise and mid-rise leggings sizing?
Same waist size. The rise affects where the band sits on your torso, not the size number. High-rise needs natural-waist measurement; mid-rise uses 1–2" below natural waist.
Should sports tops fit tight?
Tank tops and sports tees can match your normal size. Compression tops should be 1 size down from a casual tee for true performance fit.
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