Trunk comparison: BMW i4 vs Kia Stonic
Key Differences (highlighted: >10%)
The BMW i4 offers significantly more cargo length: +15.4 in (28%) with seats folded down and +11.4 in (42%) with the front seat row upright compared to the Kia Stonic. This clearly benefits longer items.
The Kia Stonic, on the other hand, has several advantages in loading geometry: the height of the trunk opening is +4.7 in (18%) larger, the depth of the trunk (distance from loading edge → trunk floor) is +3.1 in (80%) greater, and the width at the narrowest point is +6.7 in (19%) wider than in the BMW i4. These differences are significant and mainly affect loading wide or tall cargo.
Smaller differences (not highlighted): The loading edge of the Kia is 2.8 in (10%) higher above the road and the width of the trunk opening is only +2 in (5%) larger — both uncritical compared to the points mentioned above.
What impact do these differences have on practical use?
- Longer cargo: Due to the significantly greater cargo length, the BMW i4 is better suited for long items (e.g., skis, long packages, slats, furniture parts). If you frequently transport long goods, the i4 is more practical.
- Width and height of cargo: The Kia Stonic is more advantageous in everyday use for wide or bulky items. The greater interior width at the narrowest point and the higher trunk opening make it easier to load bulky suitcases, strollers, or large boxes.
- Stacking and interior depth: The greater depth (loading edge → floor) in the Stonic offers more interior height or volume near the loading edge — helpful when packing up to the loading edge or placing taller items that do not need to lie lengthwise.
- Ergonomics when lifting: The loading edge height is slightly higher in the Stonic (2.8 in, 10%), which can make lifting heavy items a bit more strenuous; however, this effect is moderate and does not exceed the 10% threshold.
In summary: For long, flat, or length-oriented cargo, the BMW i4 is the better choice. For wide, tall, or bulky everyday goods, the Kia Stonic offers the more practical loading geometry due to its larger opening, greater depth, and wider minimum width.