Our bags are deceptively large. Reach in and pull up the liner and the bag expands quite a bit. Feel free to fill it up all the way. Just make sure that you can pull the drawstrings closed tight enough that a coffee mug couldn't slip through. This ensures items won't spill out and get lost. If you put so much in the bag that you can't close it properly, we reserve the right to charge you for the overage.