How we size tents

By the Canvasdale team · Last checked 21 October 2026

A guide, not advice. Check your kit maker's figures before you buy or pack.

Our tent size calculator starts from the beds you'll actually sleep on. It doesn't use a fixed area per person, because a family on airbeds needs far more floor than the same family on thin mats. This page explains each step, and which figures are yours and which are ours.

The method

1. Your beds. You enter each bed, airbed or mat with its length and width, and how many people sleep on it.
2. Side by side. We lay the beds across the bedroom. The width is all the bed widths added together, plus a gap between each bed and at both walls.
3. Length. The longest bed, plus a gap at the head and foot.
4. Kit allowance. We multiply that bedroom area by an allowance for bags, shoes and room to move.
5. Dog. If your dog sleeps inside, we add the area of its bed.
6. Berths. We add a margin to the number of people, because berth ratings count snug, mat-sized spaces.

Which figures are yours and which are ours

Every assumption is listed under the calculator with its current value, and each has a "Changed from typical" marker when you edit it. Once our Researcher has checked makers' typical bed sizes against their published specs, choosing a bed type will fill in a typical size you can still change. Until then, we ask for your own.

What we don't do

• We don't test tents. Kit guides compare makers' published specs.
• We don't count the living area as sleeping space. Size the bedroom first, then choose the living space you want.
• We don't check pod shapes. Family tents split the floor into pods, so check each pod's inner size against the beds you'll put in it.

Limits of the method

Laying beds side by side is the simplest layout and the one most tents suit. Some families sleep head to toe, put children across the end of an airbed, or split across several pods, and those layouts can need less or more floor. Tents with sloping walls, such as bell tents and some tunnel tents, also lose usable floor near the edges. Treat the result as a starting point and compare it with the maker's sizes.

FAQs