Check sleeve, shoulder and body length
Layers need more than one number: record the shape you already know works.
Use four measurements, not one
- Measure shoulder seam to shoulder seam.
- Measure sleeve from shoulder seam to cuff.
- Measure body length from high shoulder to hem.
- Compare chest width if you plan to wear another layer underneath.
Fabric changes the result
Fabric, ribbing and cut affect fit. Measurements support a decision; they do not guarantee it.
Allow for the layer underneath
Use a hoodie that fits in the same way you intend to wear the new one. A comparison against a thin sweatshirt can mislead if you plan to layer heavily.