Work out how much bean bag filling you need from the bag’s size and shape, in litres, bags and weight.
Filling needed
How to use this tool
Enter the diameter for a round bag or the side for a square bag, in centimetres.
Choose round or square shape.
Choose filling type and a spare percentage under advanced options.
Read litres, 100-litre bags and filling weight.
Formula & worked example
A round 100 cm bean bag holds about 523.6 litres, needing 6 x 100-litre bags of EPS beads weighing about 6.28 kg before spares.
Limitations — read this before you rely on it
Geometric estimate only: real bags are sewn shapes, never filled solid, and bead density varies by brand and bead size, so weigh a sample bag when accuracy matters.
Frequently asked questions
No, most people fill to about 80–90% so the bag stays soft and mouldable; the spare allowance covers topping up, not overfilling.
Beads compress and break down with use, so a bag that feels full at first usually needs a top-up after a few weeks.
EPS beads are light and mouldable; shredded foam is heavier and firmer and holds shape longer.
Approximate it as a sphere from its widest diameter, or as a cube from its side, and treat the result as an estimate.
Yes if it is clean and dry; mix it with new filling rather than relying on flattened old beads alone.