# Outside dimensions

> Outside dimensions describe the external envelope of an assembled package, including its material thickness.

Canonical: https://dielinemaker.com/glossary/outside-dimensions
Last updated: 2026-10-26

Geometry

## What it means in packaging

They matter for shipping cartons, shelving and storage. The relationship to inside dimensions depends on the structure: doubled walls, lids and overlapping panels add different amounts of material. A single thickness formula is not valid for every box.

## A practical example

A rollover mailer wall has several board layers, so its external width cannot be inferred by adding just one caliper on each side.

## What to check

Measure the closed sample at its widest points, and use the carrier or retailer’s required measurement method.

## Use it in your project

- [Inside, outside and manufacturing dimensions](https://dielinemaker.com/learn/box-size-calculator)
- [Inside versus outside box sizes](https://dielinemaker.com/blog/box-dimensions-inside-vs-outside)

## Related terms

- [Inside dimensions](https://dielinemaker.com/glossary/inside-dimensions) — Inside dimensions describe the space within an assembled package, rather than its external footprint.
- [Caliper](https://dielinemaker.com/glossary/caliper) — Caliper is the measured thickness of a sheet material, commonly expressed in millimetres or micrometres.
- [Mailer box](https://dielinemaker.com/glossary/mailer-box) — A mailer box is a packaging format commonly assembled from one blank with a hinged lid and interlocking walls or tabs.

## Related

- [Packaging glossary](https://dielinemaker.com/glossary)