What is the Box Weight Calculator?
An empty export carton can weigh 0.5–2 kg, which adds up on a shipment and must be included in gross weight. The box weight calculator works out the board area of a regular slotted carton (RSC) and multiplies it by the combined board GSM to estimate its weight.
For the board GSM itself use the Corrugated Board Calculator; to add product, filler and tape, use the Package Weight Calculator. All calculators accept centimetres, inches or millimetres and kilograms or pounds, so you can use the units on your supplier's spec sheet.
How to use the Box Weight Calculator
- Enter the box length, width and height.
- Enter the combined board GSM or choose a ply.
- Read the board area and box weight.
Formula
Weight (kg) = board area (m²) × GSM ÷ 1,000 · RSC blank ≈ (2L + 2W + flap) × (W + H)
Example
A 40 × 30 × 30 cm RSC needs about 0.88 m² of board. At 650 GSM (5-ply) it weighs about 0.57 kg.
Typical combined GSM
| Board | Combined GSM |
|---|---|
| 3-ply light | 350–450 |
| 3-ply heavy | 450–550 |
| 5-ply | 600–900 |
| 7-ply | 1,000–1,400 |
Related packaging and shipping tools
Packaging decisions are connected: the box size sets the volumetric weight, which sets the courier bill, and the carton size decides how many fit on a pallet or in a container. These related calculators help with the next step:
- Box size calculator: inside and outside box dimensions.
- Box volume calculator: volume in cm³, litres, CBM and ft³.
- Corrugated box calculator: GSM and BCT strength.
- Cardboard sheet calculator: RSC blank size and sheet yield.
- Box dieline generator: printable cut-and-fold template.
Frequently asked questions
How much does an empty carton weigh?
Usually 0.3–2 kg depending on size and board.
What is GSM?
Grams per square metre, the weight of the paper or board.
What is combined GSM?
The total weight of all liners and flutes in the board.
Does it include tape?
No; add tape with the package weight calculator.
What box style is assumed?
A regular slotted carton (RSC).
Is the Box Weight Calculator free to use?
Yes. The Box Weight Calculator on Custom Converter is completely free, with no sign-up, no daily limit and no watermark.
Does the Box Weight Calculator work on mobile phones?
Yes. It is built mobile-first and works on Android phones, iPhones, tablets and computers in any modern browser, with no app to install.