2026-09-06 · 3 min read
Volumetric weight: how box dimensions affect shipping cost
Calculate volumetric weight with a 40 × 30 × 20 cm example. Compare actual weight, dimensional weight and carrier pricing before shipping.
Which weight will the courier bill?
Couriers charge on whichever is larger: what the parcel weighs, or what its volume implies. Enter the box, not the product — packaging counts.
How this is calculated
Volume in cubic centimetres divided by the courier's divisor, compared against actual weight; the larger number is billed. 3000 is the common divisor in Turkey, 5000 is standard for international air freight. Most couriers round up to the next whole unit, so treat a result of 10.2 as 11.
Questions
- Why is my divisor different?
- It is set in your courier contract, not by regulation. Domestic parcel services commonly use 3000; air freight uses 5000; some negotiated contracts use 4000. Check the contract before pricing a product.
- Does the packaging count?
- Yes, and it is where most costing mistakes come from. Measure the sealed box including any bulge, not the product sitting on your desk.
- Can I lower it by using a tighter box?
- Often yes. Dropping each dimension by 5 cm on a mid-size parcel can cut a full unit off the bill, which compounds across every order you ship.
Related
Follow a parcel example to understand dimensional weight, the divisor and actual weight. Turkish narration with an English companion guide.