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    Sizing Tips

    Why Your Size Varies Between Brands (And How to Decode Size Charts)

    A size 10 at Zara isn't the same as a size 10 at H&M. Here's why sizing is so inconsistent and how to navigate it like a pro.

    January 18, 20256 min readThisFits Editorial

    The Frustrating Reality of Fashion Sizing

    You're a size 8 at one store, a 12 at another, and somehow a Medium somewhere else. You're not imagining it, clothing sizes really are wildly inconsistent. Understanding why can help you stop taking it personally and start shopping smarter.

    Why Sizes Are So Different

    The "Vanity Sizing" Problem

    Over the decades, brands have gradually made their sizes larger while keeping the same number on the label. A size 8 today is significantly larger than a size 8 from 30 years ago. Why? Because customers feel better buying a smaller size number.

    Different brands have embraced vanity sizing to different degrees:

  1. Luxury brands tend to run larger (smaller size number = happier customer spending more)
  2. Fast fashion varies wildly by target demographic
  3. European sizing typically runs smaller than US sizing

    4. Target Demographics

    Brands design for their "ideal customer." A brand targeting younger shoppers might cut clothes differently than one aimed at professional women. Same size number, completely different fit.

    Manufacturing Variations

    Even within the same brand, items made in different factories can vary. Quality control isn't perfect, and a half-centimeter difference in cutting can affect fit noticeably.

    How to Decode Any Size Chart

    Step 1: Find the Actual Size Chart

    Not the "size guide" that says "S-M-L", the detailed one with centimeter measurements. It's usually linked from the product page, often in small text.

    Step 2: Compare Your Measurements

    Take your actual body measurements (see our measurement guide) and compare them to the chart. Focus on:

  4. Primary measurement: chest for tops, waist/hips for bottoms
  5. Secondary measurements: length, shoulder width, etc.

    6. Step 3: Understand the Garment Measurements

    Some brands show body measurements (your body should be this size), others show garment measurements (the actual item measures this). Big difference!

    Look for phrases like:

  6. "Garment measurements" or "Item measures"
  7. "Body measurements" or "To fit"

    8. Step 4: Factor in Fit Style

    A "relaxed fit" top will have more ease (extra room) built in than a "slim fit." Consider:

  8. Tight/Slim fit: 0-5cm ease
  9. Regular fit: 5-10cm ease
  10. Relaxed/Oversized fit: 10-20cm+ ease
    11. F

    Stop guessing. Build your profile once and never check a size chart again.

    Your fit profile knows your exact fit in every brand we cover.

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    Brand-Specific Tips

    Fast Fashion (Zara, H&M, etc.)

  11. Check reviews for sizing feedback
  12. When in doubt, size up, alterations are cheaper than returns
  13. Items often run small in shoulders and arms

    14. Premium Brands

  14. Sizing tends to be more consistent
  15. Investment in quality control pays off
  16. Size charts are usually more accurate

    17. Online-Only Brands

  17. Read reviews religiously
  18. Look for customer photos
  19. Check return policies before buying

    20. When to Size Up vs. Size Down

    Size up when:

  20. You're between sizes
  21. The fabric doesn't stretch
  22. You prefer a relaxed fit
  23. The brand is known to run small

    24. Size down when:

  24. The fabric is very stretchy
  25. Reviews consistently say it runs large
  26. You prefer a fitted look

    27. The Pro Move: Save Your Size Per Brand

    Keep a note on your phone with your size at different brands. After a successful purchase, write it down. Your future self will thank you.

    F

    Stop guessing. Build your profile once.

    Never check a size chart again. Your fit profile knows your exact size across every brand we cover.

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