Footprint and groundsheet size
A guide, not advice. Check your kit maker's figures before you buy or pack.
The calculator needs JavaScript. The worked example, sum and figures below show exactly how it works, so you can do it yourself. A guide, not advice.
Short answer
Enter the tent's ground-floor dimensions and any overlap you want to allow. The calculator adds that overlap at both ends and both sides, then shows the resulting sheet size in metric and imperial units. Check the tent maker's instructions: a sheet that protrudes can collect rain under the tent.
Worked example
| You enter | Value |
|---|---|
| Tent ground-floor length | 4 m |
| Tent ground-floor width | 2.5 m |
| Extra groundsheet beyond each side | 0 m |
Look for a groundsheet at least 4 m (13 ft 1 in) × 2.5 m (8 ft 2 in)
| Result | Value |
|---|---|
| Groundsheet length to look for | 4 m (13 ft 1 in) |
| Groundsheet width to look for | 2.5 m (8 ft 2 in) |
| Groundsheet area | 10 m² (108 ft²) |
Show the working
- Length: 4 m + 2 × 0 m = 4.00 m
- Width: 2.5 m + 2 × 0 m = 2.50 m
- Area: 4.00 × 2.50 = 10.00 m²
How it works
- Groundsheet length = tent floor length + overlap at both ends
- Groundsheet width = tent floor width + overlap at both sides
- Groundsheet area = length × width
Follow the tent maker's advice. A groundsheet that sticks out can collect rainwater under the tent; trim or fold it so it stays within the floor edge.
Our figures (adjustable)
These are our planning allowances and, once checked, typical figures with their sources. They aren't facts about your kit: change any of them in the calculator.
This calculator has no built-in defaults: every figure comes from you or your kit's own label.
What to buy
Shopping links will appear here once our retailer partners are confirmed. We don't rank kit by testing it: see our spec-based kit guides.
FAQs
Should a groundsheet be larger than the tent?
Follow the maker's instructions. If a sheet extends beyond the tent floor, rain can run onto it and pool underneath. Fold or trim any excess so it stays within the floor edge.
Can I use the tent's outer dimensions?
Use the ground-floor dimensions for the area you want to cover, not the flysheet or guy-line footprint.
Guides that use it
Do you need a tent footprint?
Whether you need a tent footprint, how to fit one under your tent without an edge sticking out, and the common mistakes to avoid.