---
title: "external dimensions: Definition and Meaning | NPSA"
description: "External dimensions are the length, width and height of a container measured on the outside."
url: https://npsa.preview.multisites.ai/glossary/external-dimensions
publisher: National Portable Storage Association (NPSA)
phone: "(816) 960-6552"
email: info@npsa.org
---

Dimensions and weight

# external dimensions

External dimensions are the length, width and height of a container measured on the outside. ISO 668 classifies series 1 freight containers by external dimensions. A standard 20-foot container is about 20 feet long, 8 feet wide and 8 feet 6 inches tall outside.

## Why it matters

Outside size decides the space you need on a site and how a truck can carry or place the unit. A carrier lists a 20-foot refrigerated container at 6,058 mm (19 feet 11 inches) long, 2,438 mm (8 feet) wide and 2,591 mm (8 feet 6 inches) high outside. Add room around the box for doors, equipment and access. A common mistake is to measure only the footprint. Check overhead clearance, ground slope, turns and gates along the delivery path. A high cube is about a foot taller. Ask the provider for the unit's outside size, and plan for extra space beyond it.

[Read: Shipping container sizes and dimensions for rental fleets](https://npsa.preview.multisites.ai/guides/container-sizes-and-dimensions)

Definition source: [iso.org](https://www.iso.org/standard/76912.html)

## Related terms

[### internal dimensions Internal dimensions are the length, width and height of the usable space inside a container. They are smaller than the outside size because of wall thickness, floor and roof structure. ISO 1496 is the authoritative document for internal container dimensions.](https://npsa.preview.multisites.ai/glossary/internal-dimensions)[### ISO 668 ISO 668 is the international standard that classifies series 1 freight containers by their external dimensions. It sets the matching ratings, which include maximum gross mass, and gives minimum internal and door opening sizes for some container types. It covers containers meant for intercontinental traffic.](https://npsa.preview.multisites.ai/glossary/iso-668)[### high cube container A high cube container is a container that is taller than standard, usually 9 feet 6 inches tall outside, compared with 8 feet 6 inches for a standard unit. It is often written HC or HQ. The extra height adds inside room.](https://npsa.preview.multisites.ai/glossary/high-cube-container)[### standard container A standard container is a regular-height dry container, usually 8 feet 6 inches tall outside, as opposed to a high cube. Carrier listings give dry 20-foot and 40-foot specifications at 8 feet 6 inches. Sellers use the word standard with some variation.](https://npsa.preview.multisites.ai/glossary/standard-container)[### overhead clearance Overhead clearance is the free vertical space above a road or drop site. Trees, power lines, bridges and roof edges limit it. A delivery truck and container need enough clear height to travel and tilt without contact. Check it along the full route.](https://npsa.preview.multisites.ai/glossary/overhead-clearance)[### turning radius Turning radius is the minimum space a vehicle needs to make a turn. A long delivery truck with a trailer needs wide, open space to turn without hitting fences, curbs or buildings. It is often given as a radius or a diameter.](https://npsa.preview.multisites.ai/glossary/turning-radius)

[All 220 terms](https://npsa.preview.multisites.ai/glossary)

For the industry

## Grow your portable storage business with NPSA

Members get event rates, the Community Forum, the directory listing and leads from this website.

[Join NPSA](https://npsa.preview.multisites.ai/join-us)[See member benefits](https://npsa.preview.multisites.ai/member-benefits)

Need storage?

## Get quotes from NPSA member companies

Tell us what you need and where. A member company that serves your area will contact you.

[Request a quote](https://npsa.preview.multisites.ai/request-a-quote)[Which unit do I need?](https://npsa.preview.multisites.ai/find-storage)