Trunk comparison: Audi Q3 vs Kia Stonic

Summary of Notable Differences

The Audi Q3 offers 11.4 in (21%) more trunk length with the seats folded down and 8.3 in (30%) more length with the front seats upright than the Kia Stonic.

The width of the trunk opening is 5.1 in (13%) larger in the Audi Q3. In contrast, the Kia Stonic has a significantly greater trunk depth (loading edge to trunk floor): +3.5 in (100%) compared to the Audi Q3. All other differences (opening height +0.4 in, loading edge height +0.8 in, narrowest width +2 in) are each below or near 10% and thus less relevant.

Impact on Usability

The greater length reserve of the Audi Q3 makes it better suited for long items such as furniture parts, long boxes, suitcases, or skis—both with folded seats and in everyday use with the front seats upright. The wider trunk opening supports loading wider or bulkier items because less maneuvering is required.

The Kia Stonic scores with its significantly greater trunk depth (loading edge to trunk floor).

This creates more usable depth/"vertical space" in the cargo area, allowing taller or bulkier items to be recessed deeper and overall making the available cargo space for irregularly shaped or stackable loads more effectively utilized.

The slightly higher loading edge (+0.8 in) and opening height (+0.4 in) are hardly noticeable in practice but can minimally complicate lifting heavy loads.

Conclusion: For long and wide cargo, the Audi Q3 is clearly advantageous. For deeper-seated or bulky, tall cargo, the Kia Stonic may have the advantage due to its greater depth.