What size stuff sack for a sleeping bag?

Stuff sacks vary from bag to bag, depending on the size and shape of the sleeping bag, as well as on the fill. Sleeping bags filled with down are more compressible than synthetic filled ones, and need lesser volume stuff sacks. You can use a regular dry sack for a down sleeping bag, except for winter weather sleeping bags where a more complex compression sack is needed to reduce volume that the sleeping bag takes up in your backpack. Here are the following size recommendations:

Synthetic insulation-filled sleeping bags don’t compress as great as down sleeping bags, so these need higher volume stuff sacks. You would need a compression stuff sack even more with synthetic insulation to compress the amount of space taken up in your backpack.