Trampoline Size Guide
Two things decide which trampoline size you actually need: how much clear space you have in the garden and how old your children are. Get those two right and the rest follows. Get them wrong and you end up with a 14ft frame wedged against the fence or a 6ft model your ten-year-old outgrows within a year.
Trampoline sizes at a glance
The table below covers every size we stock, including the garden clearance you need (measured to the outside of the enclosure, with a metre of clear space on all sides), the approximate jump mat diameter, the age range each size suits best, and the typical weight limit.
| Size | Garden space needed | Jump mat diameter (approx) | Best age range | Weight limit (approx) |
|---|---|---|---|---|
| 6ft | 9-10ft in both directions | 4ft / 1.2m | 3-6 years | 50kg |
| 8ft | 11-12ft in both directions | 5.5ft / 1.7m | 5-9 years | 75-100kg |
| 10ft | 13-15ft in both directions | 7ft / 2.1m | 8 years and up | 100-125kg |
| 12ft | 15-17ft in both directions | 8.5ft / 2.6m | 8 years and up, multi-child families | 125-150kg |
| 14ft | 17-19ft in both directions | 10ft / 3m | Teenagers, adults | 150kg |
| 16ft | 19-21ft in both directions | 12ft / 3.7m | Teenagers, serious jumpers | 150kg+ |
| Rectangular | Varies by model — allow at least 2m either side of the frame | Longer and narrower than round equivalents | All ages; gymnastics-style use | Varies by model |
How to measure your garden for a trampoline
The trampoline frame size is not the same as the space it takes up. The enclosure net adds roughly a foot to the overall diameter on each side, so a 10ft trampoline with an enclosure is closer to 11-12ft across at its widest point. Then you need clearance around that.
The rule we recommend: measure from the edge of the enclosure and add at least one metre of clear space on every side. That keeps it away from fences, garden furniture, and anything a bouncing child could reach with an outstretched arm. So for a 10ft trampoline, you want at least 13-14ft of clear, level space in both directions.
When you measure, take both directions. Gardens are rarely perfectly square. A long, narrow garden might fit a 14ft round trampoline lengthways but only give you 11ft side-to-side — which is not enough clearance. Measure the narrower axis first and work backwards from that number to find the largest size that actually fits safely.
Level ground matters too. A slope under a trampoline is not just awkward to assemble — it affects how the frame settles over time and changes how the bounce feels. A gentle slope can usually be managed with frame levelling feet (sold separately) but anything steep needs ground preparation before installation.
Here is a quick reference for the minimum clear garden space per size:
- 6ft trampoline: 9-10ft of level clear space in both directions
- 8ft trampoline: 11-12ft of level clear space in both directions
- 10ft trampoline: 13-15ft of level clear space in both directions
- 12ft trampoline: 15-17ft of level clear space in both directions
- 14ft trampoline: 17-19ft of level clear space in both directions
- 16ft trampoline: 19-21ft of level clear space in both directions
If your garden is borderline for a particular size, go down a size. A trampoline that fits properly is more useful than one that is technically there but hemmed in on all sides.
Which size for which age?
Younger children are lighter, so they do not need a large surface area to get a satisfying bounce. Older children and teenagers need more space because they jump higher, cover more ground, and lose interest quickly in anything that feels cramped.
Ages 3-5: A 6ft trampoline is plenty. The enclosure keeps the jumping area well contained, the lower weight limit (50kg) matches this age group perfectly, and a smaller mat is actually easier to control for very young children. An 8ft is also suitable if garden space allows — the extra room is useful if you have two young children who want to bounce at the same time, though one at a time is still the safety recommendation.
Ages 5-8: An 8ft trampoline is the most common choice. It gives enough room to jump confidently without the trampoline dominating a medium-sized garden. A 10ft is also worth considering if you expect a few more years of use — children in this age bracket grow fast, and what feels generous at seven can feel small by nine.
Ages 8-12: A 10ft or 12ft trampoline works well. At this age, jumping technique improves and children start going higher, so the extra mat space matters. A 12ft also gives two children more room to bounce separately, though again, solo jumping is safer.
Ages 12 and up, teenagers: A 12ft, 14ft, or 16ft trampoline. Teenagers bounce harder and go higher than younger children, and a cramped mat makes that feel uncomfortable and less safe. If the budget and garden space allow it, a 14ft is a better long-term buy for a teenage household than a 12ft.
One thing worth remembering: a trampoline that is too small gets outgrown. A trampoline that is slightly larger than strictly necessary gets used for longer. If you are uncertain between two sizes, the larger one is usually the better investment — as long as it fits the garden properly.
Round or rectangular?
Round trampolines are by far the most common choice for family gardens. The circular shape naturally pushes the bounce toward the centre, which keeps younger children in the middle of the mat and away from the edges. They work on most garden sizes, they are easier to assemble than rectangular frames, and our full trampoline range starts with round models from 6ft upward.
Rectangular trampolines are different in a few specific ways. The bounce is higher and less centralised — the mat surface is more evenly sprung, so you can jump anywhere across the mat and get a consistent response. That makes them better for gymnastics-style bouncing, seat drops, and more controlled skill practice. The trade-off is size: rectangular trampolines are longer and narrower than their round equivalents, so you need a garden with a clear run of length rather than a square-ish open area.
For most families with children under twelve, round is the practical choice. For older children or families with a specific interest in gymnastics or trampolining as a sport, rectangular models are worth a look.
Weight limits and multiple jumpers
The weight limits in the table above are per-person limits, not combined figures. They refer to how much a single jumper should weigh to use the trampoline safely. The safety recommendation for all trampolines, regardless of size, is one person on the mat at a time.
That said, weight limits do reflect the general robustness of the frame and springs. A 12ft trampoline with a 150kg limit has heavier gauge springs and a thicker frame than a 6ft model rated to 50kg. Adults can use the larger sizes — a 14ft or 16ft trampoline with a 150kg+ limit is designed to handle adult use within that weight range — but the same one-at-a-time rule applies.
By approximate size tier:
- 6ft models: 50kg per person
- 8ft models: 75-100kg per person
- 10ft models: 100-125kg per person
- 12ft models: 125-150kg per person
- 14ft models: 150kg per person
- 16ft models: 150kg or more per person
Check the specific product listing for the exact weight limit on any model you are considering. These figures are typical but individual products vary slightly.
What to check before you buy
Once you have settled on the right size, a few other things are worth confirming before placing an order.
Every trampoline we sell comes with a safety enclosure net as standard. The net attaches to the frame using poles and clips — check that the enclosure system is included and that the poles are part of the frame structure rather than added as a separate purchase. You should also check that the jump mat is included, which it is on all our models.
Spring quality affects how the bounce feels and how long the trampoline lasts. More springs does not automatically mean better — spring length and gauge matter as much as count. Longer springs typically give a softer, more forgiving bounce; shorter springs produce a firmer, snappier response. Neither is objectively better, but it is worth understanding which you are getting.
Frame gauge is the thickness of the steel used in the legs and top rails. A heavier gauge frame is more stable under use and holds up better over multiple seasons. Look for this in the product specification if durability is a priority.
The mat material is usually UV-treated polypropylene. Check that the mat has a UV treatment or UV stabiliser — mats exposed to direct sun for several summers will degrade faster without it.
Warranty terms vary. A longer warranty on the frame is a reasonable indicator of manufacturer confidence in the build quality. Check whether the springs, mat, and enclosure are covered separately from the frame, as these components sometimes have shorter warranty periods.
If you want protection during the off-season or in exposed gardens, take a look at our weather covers and anchor kits. A weather cover keeps debris off the mat and extends the life of the padding; an anchor kit secures the frame to the ground in high-wind conditions.
If you want to compare specific models across sizes, browse our full trampoline range where you can filter by size and see the full specification for each product.