Build your gym T-shirt size chart from the measured, approved sample, not from a generic chart, and split your first order so most pieces sit in the middle sizes with fewer at each end. Our gym tops run from XS to 3XL, and sizes can be mixed within the 100-piece minimum per style, so a first order can cover every size without overcommitting to any of them.
Sizing is where many first ranges go wrong. Either the published chart does not match the garment, or the order is split evenly across sizes and the extremes are left unsold. Both are easy to avoid.
Which measurements belong on the chart
A gym T-shirt size chart needs only a few measurements, taken flat with the garment laid smooth on a table. More columns tend to confuse buyers rather than help them.
| Measurement | How to take it | Why it matters |
|---|---|---|
| Chest width | Straight across, 1 cm below the armholes | The main fit decision for most buyers |
| Body length | From the highest point of the shoulder to the hem | Decides whether the top covers the waistband |
| Sleeve length | From shoulder seam to sleeve hem | Matters most on long-sleeve tops |
| Shoulder width | Seam to seam across the back | Useful for fitted cuts |
For a sleeveless top, replace sleeve length with armhole depth, measured from the shoulder point straight down to the bottom of the armhole. Customers notice a deep armhole immediately, so it deserves its own line.
Publish flat measurements and say clearly that they are garment measurements, not body measurements. If you also want to show a body chart, label it as a guide and keep it separate.
Building the chart from your sample
The most reliable chart is one you make yourself from the garment you will sell.
- Ask for the sample in a middle size, usually M.
- Measure it flat on each line of the chart above.
- Wash it once following the care label and measure again.
- Use the after-wash figures as your base.
- Ask us for the graded measurements for the other sizes in that style, and check them against a second size if you can.
Knitwear varies slightly piece to piece. Round figures to the nearest half centimetre and avoid promising exact numbers to the millimetre.
Fabric changes the fit
The same chest measurement fits differently in the two fabrics. Polyester knit has natural give but less stretch, so a regular fit feels relaxed. Polyester-elastane stretches further and recovers, so a garment with the same flat chest will feel closer and move more. If you offer one style in both fabrics, give each its own chart. Our guide to starting a gym T-shirt brand covers how to choose between them.
Splitting a first order across sizes
There is no universal ratio, but there is a sensible starting shape: heaviest in the middle, lighter at the ends. For a style of 100 pieces, a common shape looks like this:
| Size | Pieces in a 100-piece style |
|---|---|
| XS | 5 |
| S | 15 |
| M | 25 |
| L | 25 |
| XL | 15 |
| 2XL | 10 |
| 3XL | 5 |
Shift it to suit who you sell to.
A gym ordering for staff and members
Collect sizes before ordering if you can. A simple sign-up sheet at the front desk gives a real split rather than a guess. Add a few extra pieces in M and L for new members and replacements.
A sports academy
Academies often cover a wider spread: younger players in the smaller sizes and coaches at the upper end. Ask for a list by size from each team. Our adult range starts at XS, which fits many older juniors; check this against the measured sample.
A fitness brand selling online
Without a known customer list, start with the shape above and adjust after the first sell-through. Lifting-focused brands often move more L and XL; brands aimed at runners or women’s fitted cuts often move more XS to M.
Keeping sizes consistent across reorders
Customers who bought a size once expect it to fit the same next time. Keep the approved sample from your first order, and the measurements you took from it. When you reorder, ask for the same style and fabric, and check a few pieces per size on arrival against those measurements. If you change fabric or style, update the chart before the new stock goes on sale.
Some practical habits help:
- Print the size on the neck label or inside-neck print, and on the polybag if you use one.
- Pack cartons by size so stock is easy to count and store.
- Track returns by size and reason; a cluster of “too small” returns in one size tells you where the chart needs a note.
Getting your sizing started
Tell us the style, fabric and colours, your rough total per style, and either a size split or a description of who will wear the tops. See the styles and size range on our white label gym T-shirts page. We confirm the size and colour split at quotation and make a sample so you can measure it and build your chart before bulk production begins.