How to Audit Your Size Charts for Accuracy
A size chart that doesn't match the garment is worse than no chart — it actively causes the returns it was meant to prevent. Auditing them is unglamorous, cheap, and one of the highest-ROI hours you can spend.
Quick answers
- Why audit size charts?
- A wrong chart causes the returns it was meant to prevent
- Where do I start?
- Your highest-return products
- What do I measure?
- Actual production garments, not the spec sheet
- How do I know it worked?
- Return rate on that product falls
The Audit, Step by Step
| Step | What you do |
|---|---|
| 1. Pull the worst offenders | Sort products by return rate |
| 2. Measure the real garment | Physically measure production stock |
| 3. Compare to the chart | Find the discrepancy |
| 4. Correct the chart | Publish the real numbers |
| 5. Add a fit note | 'Runs small' etc. where relevant |
| 6. Re-check in 30 days | Confirm returns fell |
Notes
Measure the garment you ship, not the one you specified. Tech pack numbers are intentions. Production has tolerances, fabric relaxes, and factories drift. Pull actual stock off the shelf and measure it. The gap between spec and reality is where your returns live.
Start with the products that are already failing. Don't audit all 200 SKUs. Sort by return rate, take the worst ten, and measure those. Returns cluster heavily in a small number of products, so this is where the entire payoff sits.
Publish the garment measurements, not just body measurements. A body-measurement chart asks the customer to measure themselves accurately — which most won't do. Flat garment measurements let them compare against an item they already own and love. It's the more usable number and it audits more cleanly.
Verify the fix. After correcting a chart, watch that product's return rate for the next 30 days. If it doesn't move, the problem wasn't the chart — it's the grading, the photography, or the product itself. Confirming the fix is what separates an audit from a chore.
FAQs
How do I check if my size chart is accurate?
Physically measure actual production garments — not the tech pack spec — and compare them to your published chart. Start with your highest-return products, since returns cluster in a small number of items. Correct any discrepancies and publish the real numbers.
Should I publish garment measurements or body measurements?
Garment measurements (the flat item), ideally alongside body measurements. Most shoppers won't measure themselves accurately, but they can easily measure a garment they already own and compare — which makes it the more usable and more auditable number.
How do I know if fixing the chart worked?
Watch that product's return rate for about 30 days. If it doesn't fall, the chart wasn't the cause — look at grading, product photography, or the garment itself. Verifying the fix is the step most people skip.
Need this on your store?
Tailor Size Guide ships pre-built size charts for Shopify.