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 takes about 2 in off the height for the seal and zipper zone, multiplies width by that usable height by gusset depth, and applies a factor of about 0.40. 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 8 oz of whole-bean coffee holds far less cereal by weight.
| Product | Typical bulk density | Published values |
|---|---|---|
| Whole-bean coffee | ~0.38 g/ml | roasted beans 0.37 (Engineering ToolBox); 0.35–0.48 (Global-Pak) |
| Ground coffee | ~0.33 g/ml | 0.32 (Global-Pak); 0.40 (Engineering ToolBox) |
| Whey / plant protein powder | ~0.40 g/ml | whey 0.33 loose, 0.50 tapped; soy 0.42 / 0.59 (Bettersize) |
| Wheat flour | ~0.55 g/ml | 0.48–0.56 (Global-Pak); 0.60 (Engineering ToolBox) |
| Rolled oats | ~0.38 g/ml | 24 lb/ft³ (Global-Pak) |
| Cereal flakes | ~0.19 g/ml | 12 lb/ft³ (Global-Pak) |
| Loose-leaf tea | ~0.19 g/ml | 12 lb/ft³ (Global-Pak) |
| Dry pet kibble | ~0.42 g/ml | dog food 26 lb/ft³ (Global-Pak) |
| Gummies | ~0.70 g/ml | varies with shape and coating; weigh a measured cup of yours |
| Rice | ~0.77 g/ml | 770 kg/m³ (Engineering ToolBox) |
| Granulated sugar | ~0.80 g/ml | 800 kg/m³ (Engineering ToolBox) |
| Water-based liquid | ~1.00 g/ml | water = 1.00 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 about 0.40 times face width times bottom gusset depth times the height left after about 2 inches for the seal and zipper, 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 factor of about 0.40, applied to the height below the seal and zipper, 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. Whole-bean coffee is around 0.38, ground coffee around 0.33, protein powder around 0.40 and flour around 0.55, 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?
Stand-up pouch quotes are coming soon to PackOS Quick Quote. It prices custom roll labels today — if your pouch carries a label, upload the artwork for an instant label quote.