# Carton Cube Utilization, Void Fill and Dim Weight Calculator

> Source: https://netray.co/tools/carton-cube-utilization-void-fill-and-dim-weight-calculator
> Publisher: Netray (netray.co), AI and integration engineering for ERP and manufacturing systems.
> Section: Free Tools

## Short answer

See how full a shipping carton is, what the void costs, and whether carriers bill by volume or by weight.

## Category

supply-chain

## Industry

Packaging and Printing

## Audience

- Packaging engineer
- Logistics manager
- Shipping supervisor

## Tool

**Kind:** calculator

**Currency:** $

**Inputs:**

#### Carton inside length

**Key:** cl

**Type:** number

**Default:** 400

**Min:** 1

**Step:** 5

**Unit:** mm

#### Carton inside width

**Key:** cw

**Type:** number

**Default:** 300

**Min:** 1

**Step:** 5

**Unit:** mm

#### Carton inside height

**Key:** ch

**Type:** slider

**Default:** 250

**Min:** 50

**Max:** 600

**Step:** 5

**Unit:** mm

#### Product length

**Key:** pl

**Type:** number

**Default:** 180

**Min:** 1

**Step:** 5

**Unit:** mm

#### Product width

**Key:** pw

**Type:** number

**Default:** 140

**Min:** 1

**Step:** 5

**Unit:** mm

#### Product height

**Key:** ph

**Type:** number

**Default:** 90

**Min:** 1

**Step:** 5

**Unit:** mm

#### Units per carton

**Key:** count

**Type:** number

**Default:** 4

**Min:** 1

**Step:** 1

**Unit:** units

#### Actual packed weight

**Key:** weight

**Type:** number

**Default:** 5.5

**Min:** 0.1

**Step:** 0.1

**Unit:** kg

#### Carrier dim divisor

**Key:** divisor

**Type:** select

**Default:** 5000

**Options:**

##### 5000 (common international)

**Value:** 5000

##### 4000

**Value:** 4000

##### 6000 (common freight)

**Value:** 6000

#### Void fill cost

**Key:** fill_cost

**Type:** number

**Default:** 0.02

**Min:** 0

**Step:** 0.005

**Unit:** per litre

#### Freight rate

**Key:** rate

**Type:** number

**Default:** 3.2

**Min:** 0

**Step:** 0.1

**Unit:** per kg

**Outputs:**

#### Carton volume

**Key:** carton_l

**Expr:** cl * cw * ch / 1000000

**Format:** decimal

**Description:** Litres.

#### Product volume

**Key:** prod_l

**Expr:** pl * pw * ph * count / 1000000

**Format:** decimal

**Description:** Litres, based on bounding boxes.

#### Cube utilization

**Key:** fill_pct

**Expr:** prod_l / carton_l * 100

**Format:** percent

**Primary:** true

#### Void volume

**Key:** void_l

**Expr:** carton_l - prod_l

**Format:** decimal

#### Void-fill cost per carton

**Key:** void_cost

**Expr:** void_l * fill_cost

**Format:** currency

#### Dimensional weight

**Key:** dim_kg

**Expr:** cl * cw * ch / 1000 / divisor

**Format:** decimal

**Description:** Kilograms.

#### Billable weight

**Key:** bill_kg

**Expr:** max(weight, dim_kg)

**Format:** decimal

**Description:** Carrier charges the greater of actual and dimensional weight.

**Primary:** true

#### Freight cost per carton

**Key:** freight

**Expr:** bill_kg * rate

**Format:** currency

**Chart:**

#### Dimensional and billable weight vs carton height

**Type:** line

**X:** ch

**From:** 100

**To:** 500

**Steps:** 40

**Series:**

- dim_kg
- bill_kg

**Disclaimer:** Uses bounding boxes for product volume and a simple carrier formula. Check your carrier contract for rounding rules and minimum charges.

## Content

**Intro:** Shipping air is expensive twice: you buy void fill and you pay freight on volume. This calculator measures how full a carton is and shows whether dimensional weight is driving the freight bill.

**Sections:**

#### How to use it

**Body:** Enter the inside carton size, the size of one product, units per carton and packed weight. Pick the carrier divisor and enter void fill and freight costs. You get utilization, void volume, void-fill cost, dimensional weight and billable weight. Use the chart to see where a taller carton moves from weight-based billing to volume-based billing, then try a smaller carton size.

#### The formulas

**Body:** Cube utilization is product volume divided by carton volume. Void volume is the difference. Dimensional weight is carton volume in cubic centimetres divided by the carrier divisor, such as 5000 cm3 per kg. The carrier bills the larger of actual weight and dimensional weight. Dim weight uses the outer dimensions of the package, so allow for board thickness if you use inside dimensions as a proxy.

**Bullets:**

- Utilization = product volume / carton volume
- Void = carton volume - product volume
- Dim weight = L x W x H in cm3 / divisor
- Billable = max(actual, dim weight)

#### Common mistakes

**Body:** Using inside dimensions when the carrier measures outside underestimates dim weight slightly. Also, bounding-box volume overstates product volume for irregular shapes, which can make utilization look better than reality. Reducing carton size can hurt protection, so test drops and vibration before changing specs. Check whether your carrier rounds each dimension up to a whole centimetre or inch.

**Bullets:**

- Use outer dimensions for dim weight when possible
- Test protection after right-sizing
- Check rounding rules in the carrier contract
- Review the carton range, not just one size

**Cta:** We can help you run this across your whole item and carton master in your ERP to find the cartons costing you most.

**Faq:**

#### What is dimensional weight?

**Answer:** It is a pricing weight that reflects the space a package takes, calculated from its dimensions and a carrier divisor. If it exceeds actual weight, the carrier charges on dimensional weight instead.

#### Which divisor should I use?

**Answer:** Use the one in your carrier contract. Values like 5000 or 6000 cm3 per kg are common in international and freight use, while US carriers often quote cubic inches per pound. Check your rate card.

#### What utilization is good?

**Answer:** There is no universal target because protection needs differ. Rigid, stackable goods can reach a high fill, while fragile items need cushioning. Compare cartons within the same product family.

#### Does void-fill cost matter that much?

**Answer:** Per carton it is small, but across thousands of shipments it adds up, along with higher freight and storage space. Right-sizing usually saves more through freight than through fill material.

## Search terms

carton cube utilization calculator, void fill cost calculator, dimensional weight calculator kg, right sizing shipping cartons, billable weight calculator, package fill rate, dim weight divisor 5000, reduce shipping carton size

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