Many sellers are surprised when a light parcel is billed as 2 kg. The reason is volumetric weight: couriers charge for the space a box takes in the van, not only for what it weighs. Pick a box that is a little smaller and the same product can cost much less to ship. This guide shows how volumetric weight is worked out and how to keep it low.
What is volumetric weight?
Volumetric (or dimensional) weight is a weight worked out from the size of the parcel. The courier compares it with the actual weight on the scale and bills you for whichever is higher. So a big, light box is charged by its size, and a small, heavy box is charged by its weight.
How to calculate it
Most couriers and marketplaces in India use this formula with sizes in centimetres:
Volumetric weight (kg) = Length x Width x Height (cm) ÷ 5000
Box sizes are often given in inches. In that case a quick version of the same formula is Length x Width x Height (inches) ÷ 305. Some couriers use a different divisor (for example 4000 for some express or air services), so check the rate card in your courier or seller panel.
Most couriers then round up to the next weight slab, often 0.5 kg. Always measure the outside of the packed box, including any bulge.
Examples with real box sizes
| Box size (inches) | Volumetric weight (÷305) | Usual slab |
|---|---|---|
| 7 x 3 x 2 mailer box | 0.14 kg | 0.5 kg |
| 8 x 5 x 2 box | 0.26 kg | 0.5 kg |
| 7 x 4 x 3.5 box | 0.32 kg | 0.5 kg |
| 12 x 10 x 3 mailer box | 1.18 kg | 1.5 kg |
| 8 x 8 x 8 box | 1.68 kg | 2 kg |
| 12 x 10 x 8 box | 3.15 kg | 3.5 kg |
| 12 x 12 x 12 box | 5.67 kg | 6 kg |
Look at the 8 x 8 x 8 and 7 x 4 x 3.5 boxes. If your product fits in the smaller one, the billed weight drops from 2 kg to 0.5 kg, often a big saving on every order.
7 ways to bring courier charges down
- Use the smallest box that fits. Leave about half an inch to an inch around the product for padding, not more. Our Box Size Finder suggests sizes from your product’s measurements.
- Ship soft items in courier bags. Clothes, textiles and soft accessories do not need a box. A courier bag takes the shape of the product, so its volumetric weight stays low. See courier bag vs box for clothes.
- Choose flat boxes for flat products. Low-height mailer boxes such as 7 x 3 x 2 or 8 x 5 x 2 inch suit cosmetics, jewellery and accessories. The mailer box size guide lists all sizes.
- Use 3 ply where it is enough. A 3 ply box is lighter than 5 ply. Keep 5 ply for heavy or fragile goods. See 3 ply vs 5 ply.
- Fill gaps with light material. Shredded paper or bubble wrap protects without adding much weight, and stops you from moving to a bigger box.
- Do not let the box bulge. An overfilled box measures bigger than its label size. Pick the next size up instead of forcing the lid.
- Standardise on a few sizes. When you know which size fits each product, packing is faster and your shipping cost per order becomes predictable.
Frequently asked questions
Is volumetric weight charged even if my parcel is light?
Yes. If the volumetric weight is higher than the actual weight, most couriers bill the volumetric weight.
Do Amazon, Flipkart and Meesho use volumetric weight?
Their shipping fees also look at package size and weight. The exact rules and slabs differ and change from time to time, so check the fee section of your seller panel.
Should I measure in inches or centimetres?
Either works. Use ÷305 for inches or ÷5000 for centimetres (or the divisor your courier gives).
Can I get boxes in bulk?
Yes. Every SecureShip order has free delivery across India and a GST invoice. For regular volumes you can request a bulk quote.
