How gusset depth becomes volume
The gusset is the fold at the bottom (or sides) of a pouch that opens up when filled, turning a flat bag into a container that stands. Its depth is the biggest lever on capacity: a deeper bottom gusset opens into a wider base and holds more, at the cost of a little effective height. This calculator estimates how much a stand-up pouch holds from its flat width, height, and gusset depth.
A filled pouch is not a clean rectangular prism — the top tapers to the seal and the gusset only opens partway — so a realistic estimate multiplies width by gusset depth by height and applies a fill factor of about 0.63. That gets you to the right pouch size; always confirm with a real fill test before committing to tooling, because settling and headspace shift the number.
Turning volume into fill weight
Volume is only half the answer — what you actually sell is a weight. Multiply the volume by your product’s bulk density to get the fill weight. Densities vary widely, which is why the same pouch that holds 12 oz of coffee holds far less granola by weight.
| Product | Typical bulk density |
|---|---|
| Whole-bean coffee | ~0.35 g/ml |
| Granola / puffed snacks | ~0.20–0.30 g/ml |
| Protein / drink powder | ~0.5–0.7 g/ml |
| Gummies | ~0.7–0.9 g/ml |
Densities are typical starting points — measure your own product. For the shapes and where the gusset sits, read what is a gusset on a pouch.
Questions
How much does a stand-up pouch hold?
Estimate usable volume as face width times bottom gusset depth times height, with a fill factor of about 0.63 because the filled pouch is not a perfect box. The calculator above does this and converts the result to milliliters and fluid ounces, and to a fill weight if you enter your product density.
How does gusset depth affect pouch volume?
A deeper bottom gusset opens into a wider base and holds noticeably more, trading away a little effective height. It is the strongest single lever on capacity, which is why sizing a pouch means choosing width, height, and gusset depth together.
Why is my pouch volume just an estimate?
A filled pouch tapers toward its top seal and the gusset only opens partway, so no simple formula is exact. The fill factor of about 0.63 captures typical real-world behavior, but settling, headspace, and the filling method all shift it, so a physical fill test is the final word before tooling.
How do I convert pouch volume to fill weight?
Multiply the volume in milliliters by your product bulk density in grams per milliliter. Coffee is around 0.35, granola around 0.25, and powders around 0.5 to 0.7, so the same pouch holds very different weights of different products. Measure your own product to be sure.
What size gusset do I need for a given weight?
Work backwards: divide your target fill weight by the product density to get the volume you need, then adjust width, height, and gusset depth until the estimate meets it. Deeper gussets add volume fastest. Enter values in the calculator until the fill weight matches your target.
Found your size? Get it made.
PackOS quotes stand-up pouches from your spec — upload artwork or start from dimensions.