Trunk comparison: Audi A6 Avant vs Tesla Model 3

Summary of the main differences
The most noticeable difference is the height of the trunk opening: The Audi A6 Avant's opening is
larger than that of the Tesla Model 3. This means there is significantly more vertical space available to load bulky or tall items. Also notably different is the depth from the loading edge to the trunk floor: The Tesla Model 3 has
more depth here than the Audi, meaning a much deeper load floor or a larger "recess" behind the loading edge.
Impact on usability
The higher trunk opening of the Audi makes it easier to load and unload bulky, tall items (crates, boxes, soccer balls, tall bike racks, placeable furniture parts). Large, angular items are easier to maneuver because there is more clearance height and lifting can be done in one step. The significantly greater depth in the Tesla results in more usable space between the loading edge and floor — this increases the volume for flat-lying or stackable cargo and can be advantageous when transporting suitcases or shopping bags. At the same time, a deeper load floor also means: items lie lower and are harder to reach; heavy loads often have to be lifted over the higher loading edge and then lowered into a deeper recess, which can make handling more difficult. Because the Tesla's loading edge is also somewhat higher above the road, the physical strain when lifting heavy items increases.
Other, smaller differences
The remaining differences (length and width measurements) are under 10%: The Audi offers slightly more length with the first row of seats upright (+3.5 in/5% and +3.9 in/9%) and somewhat more width at the narrowest point (+2 in/5%) as well as a slightly larger opening width (+1.6 in/4%). The Tesla's loading edge is +1.2 in (5%) higher above the road. These deviations only moderately improve everyday usability: the Audi is slightly more flexible for longer/slightly wider items, while the Tesla design scores with the deeper recess for flatter stacks but seems less ergonomic when lifting heavy objects.