A puffer's chest includes its volume
The outer chest of a down jacket is the distance around the quilted shell, not the circumference of your body. Dior's cropped reversible puffer appears with a 116 cm chest at XS and a 49 cm garment length. That is a deliberately roomy result because the jacket contains fill and is intended to be worn over other clothes. A tailored Bar jacket in nearby sizes uses a much closer chest row. Comparing one with the other without separating construction leads to the mistaken conclusion that the puffer is two sizes too large. The puffer is wide because the product is a complete outer layer.
Shoulder and sleeve room decide layering
A padded jacket adds thickness around the upper arm and across the back. Even when the chest looks generous, the shoulder or sleeve can restrict forward reach if it was cut for a light layer. Put on the thickest sweater or hoodie you plan to use and compare its shoulder and upper-arm outline with the jacket. Ask for shoulder seam to seam and sleeve length with the start point. A sleeve measured including the shoulder will look much longer than an outside sleeve and cannot be compared directly. The right figure is the one taken in the same convention as the garment you already own.
A short puffer and a long coat are separate decisions
Dior outerwear spans cropped puffer shapes and tailored jackets with different hem positions. A 49 cm cropped puffer leaves more of the lower body uncovered than a garment that finishes near the hip; that is a silhouette choice rather than a size defect. Measure centre-back length and compare it with a jacket whose hem sits where you want it. Then check whether the shorter body is balanced by the sleeve and shoulder. If the piece is reversible, inspect both finishes and record the colourway, because the same nominal jacket may show different seams, pockets or closures depending on the side.
Build a padded-jacket checklist
Record outer chest, shoulder, back length, sleeve and relaxed hem; repeat the chest reading without compressing the fill. Add the layer you intend to wear and note whether reaching forward pulls at the upper back. Confirm the hood, collar, zip and cuff construction from front, back and side photographs. Dior notes that garment measurements can vary by about 2 cm, so do not reject a jacket over a single millimetre, but do treat a two-centimetre shoulder difference as meaningful. The combination of measurements, layer and construction is the workable basis for an answer.
When the cropped length is intentional
A short puffer should not be judged by the length of a tailored coat. Its 49 cm garment row belongs to a different design goal, and the visible hem may be part of the style rather than a sign that the jacket is too small. The useful comparison is against another cropped jacket whose hem you like. If you need more lower-body coverage, choose a longer silhouette instead of moving up in the cropped one. That distinction protects the shoulder and sleeve fit while acknowledging that no amount of extra chest width changes where the hem stops.