I purchased a Sandisk 32GB Class 4 card just 1 week before this one. That had 29.7GB of usable space. This one has only 29.29GB. Why 2 cards of the same model, capacity and bus speed have different free space, I don't know. Still, it's better than Strontium, which has only 29.11GB of free space. The slow speed of the Class 4 card doesn't matter for my purposes.