Develop & order
How to measure a T-shirt: points of measure, size charts and tolerances
Garments are measured flat on a table, without stretching, at defined points of measure (POMs) such as chest ½ width, body length and sleeve length. A size chart lists each POM for every size with a tolerance (+/−). Knits are usually given wider tolerances than woven garments because the fabric stretches.
Key takeaways
- Measure flat and relaxed. Lay the garment on a table, smooth it without pulling, and measure edge to edge.
- Most size charts use ½ measurements for chest, waist and hem, meaning the flat width and not the full circumference.
- Every POM needs a written measuring method, a value per size and a tolerance.
- Measure samples before and after washing to see how the knit settles.
A size chart is only as good as the way it is measured. Two people can measure the same T-shirt and get chest widths 2 cm apart if one smooths the fabric and the other pulls it. The fix is simple: define each point of measure, measure flat, and agree tolerances.
1. How to measure: the basic rules
- Lay the garment flat on a hard table, front facing up
- Close zips and buttons, and smooth out creases without stretching
- Use a flexible tape measure in cm (or the unit in your spec)
- Measure edge to edge at the defined points
- Measure ½ widths straight across, perpendicular to the centre front
- Record the garment’s state: unwashed, or after a stated wash method
- Measure several pieces per size, not just one
2. Key points of measure for a T-shirt
| POM | How to measure |
|---|---|
| Chest ½ width | Straight across, a stated distance below the armhole (e.g. 2.5 cm below) |
| Body length | From high point shoulder (HPS) to bottom hem |
| Shoulder width | Seam to seam across the back |
| Sleeve length | Shoulder seam to sleeve hem edge |
| Sleeve opening ½ | Straight across the sleeve hem |
| Armhole (straight) | Shoulder point to underarm point |
| Neck width | Edge to edge across the neck opening, seam to seam |
| Front neck drop | From the HPS line down to the top of the front collar |
| Back neck drop | From the HPS line down to the top of the back collar |
| Bottom hem ½ width | Straight across the hem edge |
| Collar rib height | Edge of rib to seam |
3. Extra points for hoodies, polos and sets
| Garment | Additional POMs |
|---|---|
| Hoodie / sweatshirt | Hood height and width, cuff ½ width and height, hem rib height, pocket position and size, zip length |
| Polo shirt | Collar length and point, placket length and width, button spacing, side vent length |
| Pants / joggers | Waist ½ relaxed and extended, hip ½, front and back rise, inseam, thigh ½, leg opening ½, waistband height |
For elastic waistbands and rib cuffs, give two values, relaxed and extended (stretched to its limit). That checks both the look and whether the garment can be put on.
4. How to build a size chart
A useful size chart has five things: a POM code and name (for example A, Chest ½), a short measuring method or sketch, a value for each size (S, M, L and so on), a tolerance (+/−), and a grade rule, which is the change between sizes.
At Jehotex the base pattern is drafted and graded in CAD across your size range, and the graded pattern is checked against the size chart before production. If the fabric shrinks, the shrinkage allowance is built into the pattern so the finished, washed garment meets the chart. See why knit garments shrink.
5. Setting tolerances for knitwear
Knit fabric stretches and recovers, so knits usually get wider tolerances than woven garments. Don’t copy numbers from another chart. Set them by the size of the dimension and how much it matters:
| POM type | Tolerance approach |
|---|---|
| Large dimensions (chest, length, hem) | Wider, since they vary more with stretch and relaxation |
| Medium dimensions (sleeve, shoulder) | Moderate |
| Small or critical dimensions (neck width, neck drop, collar height, placket) | Tight, because small errors are very visible |
| Functional dimensions (waist extended, neck stretch for head opening) | Defined as a minimum, not just +/− |
Agree the final tolerances during fit sampling, when you can see how your fabric behaves.
6. Common measuring mistakes
- Measuring chest at the armhole seam instead of the stated distance below it
- Measuring a full circumference when the chart uses ½ widths
- Pulling the hem straight on a garment that has twisted
- Measuring sleeves along the fold instead of the top edge
- Mixing HPS and centre-back body lengths
- Measuring a freshly pressed garment and comparing it to a washed one
7. Measurements in quality control
Measurements get checked at several stages: the graded pattern against the size chart, first pieces off the line, and finished garments in final inspection. A measurement outside tolerance is commonly treated as a major defect in AQL inspection. See knitwear quality control and our quality control process.
Final thoughts
Consistent measuring gives buyer and factory a shared language. Write down how each POM is measured, measure flat and relaxed, give knits realistic tolerances, and check washed samples. Most “wrong size” disputes go away once both sides measure the same way. Start with a clear tech pack or talk to us through our OEM/ODM page.