Polyfill Stuffing Weight Calculator
Calculate how much polyfill stuffing you need for a plush toy.
Enter toy volume and desired firmness to get the weight in grams and ounces.
Polyfill (polyester fiberfill) is sold by weight, not volume. To estimate how much you need, convert from your toy’s volume to grams based on how densely you want to fill it.
Density by firmness:
- Soft / floppy (teddy bears, decorative cushions): 10 g/L
- Medium (most stuffed animals, pillows): 20 g/L
- Firm (play balls, poseable toys): 35 g/L
The formula:
weight_g = volume_L x density_g_per_L
For irregular shapes (a bear body is not a box), estimate volume by imagining the smallest box that would contain the toy, then multiply by 0.65 for actual body volume. A 20 x 15 x 10 cm bear body box is 3 L; multiply by 0.65 gives about 2 L of stuffable space.
Practical notes:
Polyfill compresses significantly when first stuffed and then relaxes over hours. Toys often feel slightly firmer right after stuffing and soften to their final feel overnight. If you want a consistently firm toy, stuff it 15-20% more than the calculation suggests and check the next day.
Bags are commonly sold in 100 g, 250 g, 500 g, and 1 kg sizes. Always round up to the nearest bag size. Leftover polyfill stores easily and keeps indefinitely in a sealed bag.