Bulk bag size calculator.
Enter how much product goes in each bag and its bulk density. The calculator suggests the bag height for your chosen base, with 10% headroom for settling and filling.
How the calculation works
Height = (fill weight ÷ bulk density) × 1.10 ÷ base area. Volume in m³ is weight in tonnes divided by bulk density in t/m³; the 10% headroom allows for the bag bulging and the product settling. Round the height up to the next 5 cm.
Always confirm with a trial fill, and choose a safe working load (SWL) at or above your fill weight — 5:1 for single-trip and 6:1 for multi-trip bags (see our safety factor guide).
Frequently asked questions
What size bulk bag do I need for 1 ton of sand?
Sand at about 1.6 t/m³ fills 0.63 m³ per tonne, so a 90 × 90 cm base needs only about 85–90 cm height. Many sand bags are 90 × 90 × 90 cm with a 1,000–1,500 kg SWL.
What is the standard bulk bag size?
The most common FIBC is 90 × 90 × 100–120 cm (35 × 35 × 40–47 in), which fits a 48 × 40 in or 1,200 × 1,000 mm pallet and holds 1 tonne of grain-density product.
How do I find the bulk density of my product?
Fill a container of known volume (e.g. a 10 L bucket) loosely, weigh it, and divide the weight by the volume. Fine powders may also settle by 10–20% in transit.
Can you make custom bulk bag sizes?
Yes. Base, height, top and bottom spouts, liners, coating and printing are all made to order. Send your fill weight and product for a recommendation.
More calculators
Need the bags themselves? Browse FIBC Bulk Bags or request a factory quote.
Tell us what you pack.
We’ll engineer the bag.
Share your product, fill weight and destination. A packaging engineer replies with a construction, price and lead time — usually within 8 hours.