How to size a stand-up pouch from fill weight
A typical pouch size calculator asks for a volume — but when you’re sourcing packaging you usually know the weight you want to sell, not the cubic inches it occupies. The bridge between them is bulk density: how much a product weighs per unit of volume. Whole coffee beans, ground coffee, protein powder, and gummies all pack differently, so the same 12 oz needs very different pouches. This tool starts from your product and target weight, converts to volume with a published density, and recommends a pouch size.
Why weight-to-volume is the honest starting point
Fill weight divided by bulk density gives fill volume. Add headspace — the empty room a pouch needs to seal cleanly and let contents settle — and you have the internal volume the pouch must hold. From there, a filled stand-up pouch holds about 0.40 × width × (height − 2 in) × gusset: the 2 in is the seal and zipper zone, and the 0.40 reflects a base that opens to the gusset depth and tapers to nothing at the top seal. The calculator checks that against common stock sizes and also gives a custom size at conventional proportions (usable height about 1.2× the width, gusset about 0.55× the width). It’s a starting point, not a spec: grind, moisture, and settling all move real capacity, so a physical fill test confirms it.
From recommended size to a real pouch
Once you have a target size, snap it to the nearest stock size on the sizes chart or take the exact dimensions to a converter. If you want to check the capacity of a specific pouch you already have in mind, the gusset volume calculator runs the math the other direction — width, height, and gusset in, fill volume out.
Bulk densities used
| 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 |
Questions
How do I calculate what size stand-up pouch I need?
Start from your fill weight and the product’s bulk density: weight divided by density gives the fill volume. Add headspace, then match that volume to a pouch size (a stand-up pouch holds about 0.40 × width × (height − 2 in for the seal and zipper) × gusset). The calculator does this from your product and target weight; confirm the result with a physical fill test.
How much does a stand-up pouch hold?
It depends on the pouch dimensions and the product’s density. A pouch’s fill volume is about 0.40 × width × (height minus about 2 inches for the seal and zipper) × gusset depth, and how much weight that holds depends on how dense the product is — the same pouch holds far more grams of gummies than of loose tea. Enter your product and target weight to size a pouch, or use the gusset volume calculator to check a specific size.
What is bulk density and why does it matter for pouch sizing?
Bulk density is how much a product weighs per unit of volume, including the air gaps between pieces. It is the reason a pouch sized for coffee beans is wrong for protein powder at the same weight. Using a realistic density — not a guess — is what turns a target weight into a correct pouch size.
How much headspace should a pouch have?
Typically around 15–20% of the fill volume, more for bulky or settling products and less for dense, stable ones. Headspace lets the pouch seal cleanly, accommodates settling in transit, and keeps the pack from looking overstuffed. The calculator lets you pick a headspace band and folds it into the recommended size.
Are the bulk densities in this tool exact?
They are typical published values, not exact for your specific product. Grind, moisture, formulation, and how the product settles all shift real density, so treat the recommended size as a starting point and confirm with a fill test before committing to tooling or a large order.
Sized your pouch?
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