How to Get the Perfect Fit When Buying Clothes Online

Buying clothes online can feel risky when you can’t try anything on — and with one-of-a-kind pieces there’s no “order two sizes.” The good news: with a tape measure and five minutes, you can buy pre-loved tops and dresses that fit first time. Here’s exactly how to find your size buying clothes online.

Quick answer: don’t trust the size label alone. Measure your bust, waist and hips once, measure a top you already love, and match those numbers to the garment measurements on the listing. Numbers never lie the way labels do.

Why you can’t trust the size label

A “Medium” means something different in every brand, country and decade. Vintage sizing in particular runs small. That’s why every listing at The Thrifty Closet includes actual garment measurements in centimetres — the only reliable way to know how something will fit.

Step 1: Measure yourself

Grab a soft tape measure, wear light clothing, and keep the tape snug but not tight:

• Bust – around the fullest part of your chest
• Waist – around the narrowest part of your torso
• Hips – around the fullest part, feet together
• Length – from your shoulder to where you want a top or dress to end

Write these down once and keep them in your phone — you’ll use them every time you shop.

Step 2: Measure a garment you already love

This is the secret most people skip. Lay a top that fits you perfectly on a flat surface and measure it:

• Pit-to-pit (armpit to armpit) × 2 = the chest measurement
• Length from the highest shoulder point to the hem
• Sleeve from shoulder seam to cuff

Now you have a target. Match these to the listing and the fit is predictable.

Step 3: Use a size guide as a starting point

Use general sizing only as a rough guide, then confirm with the measurements:

Size	Bust (cm)	Waist (cm)
XS	78–82	60–64
S	82–87	64–69
M	87–92	69–74
L	92–98	74–80
XL	98–104	80–86

These ranges vary between brands, so always let the garment measurement decide.

Step 4: Think about fit and fabric

The same measurements can feel different depending on the cut and cloth:

• Fitted / bodycon styles should sit close to your body measurements.
• Relaxed / boxy styles need a few centimetres of ease for the look to work.
• Stretch fabrics (with elastane) are forgiving; rigid wovens are not — size up if you’re between.

Step 5: Check the condition grade

Fit isn’t only about size — condition matters too. Every piece is graded NWT, Excellent, Good or Fair, and the photos and notes flag any stretching or shrinkage, so there are no surprises. (More on grades in our quality guide.)

How to measure a dress or bodycon

Tops aren’t the only thing worth measuring. For a dress or bodycon, also check:

• Bust and waist laid flat (double each for the full measurement)
• Hip, measured about 20 cm below the waist
• Total length from shoulder to hem, so you know exactly where it will sit on you

Common fit mistakes to avoid

• Trusting the size label instead of the centimetres.
• Forgetting about fabric — rigid wovens need more ease than stretchy knits.
• Ignoring length, which is what makes a crop top or dress look right (or wrong) on your frame.
• Not measuring a favourite you already own — it’s the single best reference point you have.

What to do if you’re still unsure

If a measurement lands right on the edge of your range, message us before you order. With one-of-a-kind pieces we’d far rather help you get it right than have something come back — we’re always happy to talk you through the fit.

Frequently asked questions

What if I’m between two sizes?

Go by the garment measurement and the fabric. For stretchy, fitted styles size down; for rigid or boxy styles size up.

How do I measure my bust correctly?

Wrap a soft tape around the fullest part of your chest, keep it level front to back, and breathe normally. Don’t pull it tight.

Can I return a piece if it doesn’t fit?

Because every item is one-of-a-kind, please check the measurements carefully before ordering and reach out if you’re unsure — see our shipping & returns page for details.

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Measure once, shop with confidence, and every pre-loved piece will fit like it was made for you.

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