How fits are checked

Every tent floor, peak and vestibule, and every pad, cot and pack, is drawn at the size its maker lists. The spec sheet gives each number as the maker wrote it, with the page it came from and the date it was checked.

Typical sizes, such as a regular pad or a queen air mattress, are matched to makers' size charts and marked as typical. Spec-sheet floors can run small; where a reviewer measured a floor, the tent's page gives both.

Each floor is drawn from its listed length and its width at the head and the foot, so a tapered floor narrows toward the foot. Vestibules are drawn with their listed area, as half-ellipses off the wall (real ones are closer to triangles). On a shelter pitched with trekking poles, they're the ground under the fly outside the floor.

Makers list the peak height, not the shape of the walls. TentCheck models the roof from the floor, the peak and how the poles hold the walls: near-vertical for a cabin, curved for a dome, straight for a trekking-pole shelter. The shapes are tuned against makers' photos and drawings, not measured, and are least certain near the floor.

• Fits An inch or more to every wall, to the sloping roof and to everything else on the floor.
• Fits, but tight Inside the floor, but under an inch from a wall, or the top of a pad, cot or pack within an inch of the sloping roof. The fabric gives, but a wet wall wets what touches it.
• Doesn't fit Past the wall, or on top of something else.

On the tent pages, the pad pages and in "Which tents fit?", pads lie side by side, edge to edge, along the tent or across it, slid from the head end to the first spot where they fit with an inch to every wall, or, where they don't, to the spot that comes closest. On Tent fit you place them yourself.

Sit-up room is the roof over the middle of the pad, less the pad (about an inch) and a 35 in sitting height, about an average adult's (ANSUR II, the US Army's body survey). Headroom is how much of the floor has the roof 12, 24 and 36 in over it. Standing room is the floor where the roof is at least the person's height: 5 ft 9 in, the average US man (CDC), unless you set your own.

For tall sleepers, a person built from the ANSUR II body measurements, scaled to their height, lies on their back on the pad, the head an inch in from its end. Their head and feet need an inch from the sloping end walls. A pillow or a lofty sleeping bag takes a little more.

Gear in a vestibule has to clear the fly over it by an inch and leave a way out at the door as wide as your shoulders: 20 in unless you set your own, the average man's shoulder breadth in ANSUR II (17.7 in for the average woman).

NEMO publishes which pads fit each of its tents (What size sleeping pads fit in your tent?, checked 2026-10-22). For the same pads in the same tents, TentCheck gives the same answer in 16 of 21 cases. In the other 5, it says "Fits, but tight" where NEMO says they fit: each is within an inch of a wall or the sloping roof, where TentCheck warns. It calls nothing a fit that NEMO says doesn't fit, and rules out nothing that NEMO says does.

Typical sizes: regular pads are 20 in wide, wide pads are 25 in wide, XL wide pads are 30 in wide, matched to NEMO's Roamer XL Wide. NEMO's "we do not recommend it" counts as no. Its Roamer Double rows are left out, because the typical double pad isn't the Roamer Double's size. A test holds the model to this chart, so a change to either shows up.

• Diagonal layouts: pads turn only a quarter turn.
• Side sleepers, pillows and lofty sleeping bags, and shoulders against the side walls.
• Cot legs and crossbars: gear counts as fitting under a cot 12 in or taller if it is at least 3 in shorter than the cot.
• Floors that aren't four-sided, such as hexagons.

Treat a result within an inch or two as too close to call, and measure your own gear when a fit is close. The terms say the same: these are planning estimates.