The right shredder bag size for a Bonsen shredder depends on the basket/canister size , not just the brand. Bonsen home-office models commonly use a 4-gallon basket, and small shredder bags that fit most 6–7 gallon shredders are often around a 47.5-inch top circumference.

What to use

For many Bonsen small office units, a 10-gallon shredder bag is a common match if the basket opening is under about 48 inches around the top. If your Bonsen shredder has a 4-gallon wastebasket, you may need a smaller bag than that, so measuring the bin is the safest way to avoid a loose or oversized fit.

How to check size

Measure:

  1. The height from the floor to the top of the receptacle area.
  2. The circumference around the bin or suspension frame where the bag hangs.

A general fitting guide says bag height is about receptacle height × 1.3 , and bag circumference is based on the bin/frame measurement, with some extra room allowed for fan-gusset bags.

Practical rule

  • 4-gallon Bonsen shredder: usually needs a small bag, measured to fit the bin precisely.
  • 6–7 gallon shredders: often fit a 10-gallon shredder bag with about a 47.5-inch circumference.
  • Larger office shredders: may need medium or commercial bags depending on throat width and cabinet size.

Best next step

Check the exact Bonsen model number on the machine or manual, then match it to the basket dimensions. If you want, I can help you figure out the exact bag size from the model number or basket measurements.