ASOS and Zara use different sizing approaches, product ranges and fit styles. This guide helps you compare ASOS vs Zara sizing without relying on guesswork or one-size-fits-all advice.
Key takeaway
When comparing ASOS and Zara, keep the garment category fixed and compare the same measurements in both calculators. A UK label alone is not enough to predict fit.
The quick answer
ASOS carries a broad mix of styles and fit ranges, while Zara is more focused on its own collections and trend-led cuts. That means sizing can vary more by product than by brand name alone.
If you are buying jeans, trousers or dresses, your waist and hip measurements are the first place to look. For tops and jackets, compare bust or chest, shoulders and sleeve length where available.
- Use ASOS and Zara calculators separately, then compare the closest-size estimate.
- Check whether the product is fitted, relaxed, oversized or stretch.
- Use UK, US and EU labels as guides, not guarantees.
UK sizing is not always identical
Two garments can both be labelled UK 10 and still fit differently. Brands choose their own fit models and grading rules, and product categories do not scale evenly. A fitted Zara dress may feel different from an ASOS relaxed dress even if both share the same size label.
SizeWise is designed to reduce that uncertainty by comparing measurements with brand and category-specific rows from the workbook data.
Best measurements to compare
For dresses, compare bust, waist and hips together. For jeans, compare waist, hips and inseam. For shirts and jackets, include sleeve length or shoulders if you have those measurements. More relevant measurements usually produce a more useful estimate.
Related SizeWise tools
Frequently asked questions
Is ASOS sizing the same as Zara?
No size comparison is exact. ASOS and Zara can fit differently by product category, cut and fabric, so compare measurements before choosing.
Can I convert ASOS sizes to Zara sizes?
You can compare estimated sizes using the ASOS and Zara calculators, but treat the conversion as an estimate rather than a guaranteed equivalent.