Trunk comparison: Audi Q3 vs Skoda Fabia

Key Differences
The Audi Q3 offers significantly more cargo length: with the seats folded down, the trunk of the Q3 is +9.8 in (18%) longer, and with the first row of seats upright, it is +6.3 in (22%) longer than the Škoda Fabia. The width of the trunk opening is also larger in the Q3: +4.7 in (12%).
In contrast, the Fabia has a greater installation depth (distance from loading edge to trunk floor): this is +3.9 in (111%) larger in the Škoda.
Smaller differences without emphasis are that the loading edge of the Q3 is about 2.8 in (10%) higher and the narrowest trunk width in the Q3 is only about 2.8 in (8%) wider; the trunk opening of the Fabia is about 1.6 in (5%) higher.
Implications for Usability
Practically, this means: the Audi Q3 clearly has the advantage for long or wide loads — long items (e.g., boards, skis, furniture parts) fit better in the Q3, and the larger opening width makes loading wide packages or boxes easier.
The higher loading edge height of the Q3 makes lifting heavier items somewhat more strenuous than in the Fabia.
The Škoda Fabia scores with its significantly greater depth from the loading lip to the trunk floor. This creates more usable volume vertically and is better suited for stacking or for taller items that need to be placed deep inside.
Additionally, the slightly lower loading edge in the Fabia is advantageous when frequently lifting heavy loads.
In summary: for long and wide cargo as well as comfort when storing large items, the Audi Q3 is better suited; for deeper volume, easier lifting, and stackable cargo, the Škoda Fabia offers practical advantages.