Skip to content
100% Kiwi whānau business · Helping New Zealanders move more freely since 2005
100% Kiwi whānau business · Since 2005
⭐ SuperGold Card accepted 📞 022 022 9956 ✉ info@mobilityplus.co.nz
SuperGold Card accepted here A registered SuperGold business partner

Measuring Guides | Wheelchair & Toilet Seat Raiser Sizing

Getting the size right is the difference between equipment that helps and equipment that goes back in the box. These two guides walk you through exactly what to measure, in plain language, with a diagram for each. Both print out on a single A4 page if you'd rather take a sheet and a tape measure to the bathroom.

Not sure once you've measured? Ring Kellie on 022 022 9956 or email info@mobilityplus.co.nz with your numbers. We would far rather spend five minutes helping you choose than process a return.

Will this wheelchair fit? Measure first — it takes two minutes

Seat width is the single most common reason a wheelchair gets sent back. Too narrow and it rubs and hurts; too wide and the user slumps sideways and can’t reach the wheels properly. Grab a tape measure and check these four numbers before you order.

Wheelchair measuring diagram Front view showing seat width A measured between the inside faces of the armrests, and side view showing seat depth B, floor to seat height C, and backrest height D. FRONT VIEW A Seat width inside face to inside face SIDE VIEW B C D
Not to scale — use it to find the four measurements, not to judge proportions.
  1. A
    Seat width

    Sit the user on a firm chair, knees together, wearing their usual clothes. Measure straight across the widest point of the hips or thighs. That measurement is the seat width to order — there is nothing to add. If it falls between two sizes, take the larger one.

  2. B
    Seat depth

    Sitting, measure from the back of the bottom to the back of the knee. Take 5cm off. A seat that runs right to the knee presses on the back of the leg and cuts circulation.

  3. C
    Floor to seat height

    Measure from the heel to the back of the knee with shoes on. The footplates need to sit at that height with thighs level. If the user will push themselves along with their feet, you want a lower seat so both heels reach the floor.

  4. D
    Backrest height

    For a self-propelled chair, the back should finish just below the shoulder blades so the arms swing freely. For a transit chair pushed by someone else, a higher back gives more support.

Print the measuring sheet

Still not sure? Ring Kellie on 022 022 9956 or send us the measurements and we’ll tell you honestly which chair to buy — or that none of ours is right. This is a general guide, not a clinical assessment: if the user has pressure areas, a spinal condition or sits asymmetrically, please get an occupational therapist involved.

Will it fit your toilet? Three measurements, two minutes

Raised toilet seats can’t be returned for change of mind — they’re a hygiene item — so it’s worth getting the tape measure out first. Nearly every one that comes back to us fails on one of three things: the height is wrong, it won’t grip the pan, or the opening is too narrow to reach through. Here’s how to rule all three out.

Toilet measuring diagram Side view of a toilet showing measurement 1, floor to the top of the existing seat. Top view of the pan showing measurement 2, width across the widest point, and measurement 3, length from the back of the pan to the front tip. A detail view shows the overhanging rim lip that clamp-on brackets need to grip. SIDE VIEW 1 Floor to seat top most NZ toilets: 40–43cm TOP VIEW OF THE PAN 2 3 2 = width  ·  3 = length measure the pan itself, seat lifted THE BIT PEOPLE MISS — THE RIM LIP ✓ Lip overhangs — clamps grip ✗ Skirted, flush sides — nothing to grip
  1. 1
    How much extra height do you actually need?

    Measure the floor to the top of the seat you have now (most NZ toilets sit at 40–43cm). Then sit on a dining chair the user gets out of comfortably and measure that seat height. The difference is the raise you need. Higher is not better — if the feet dangle, standing up gets harder, not easier. When you’re between two sizes, take the lower one.

  2. 23
    Measure the pan, not the seat

    Lift the seat and lid out of the way. Measure across the pan at its widest point, then from the back of the pan (where it meets the cistern) to the very front tip. Check both against the outside dimensions listed on the raiser you’re looking at — the raiser must sit on the pan rim, not perch on it.

  3. 4
    Run a finger under the rim

    Every raiser we sell clamps onto the pan. Those clamps need an overhanging lip with a gap underneath. Older rounded and oval pans have this and are the easy case. Modern square, D-shaped or “skirted” pans, where the sides run straight down to the floor, often have nothing to grab — a clamp-on raiser will slide on those. An over-toilet frame is the answer there: it stands on the floor over the top, so pan shape doesn’t matter at all.

Work out your raise height

How our raisers compare

Raiser Raise heights Opening (W × L) Max user How it fixes on Best for
Goldfern Raised Toilet Seat$99.00 5cm, 10cm, 15cm 14–15 × 26–27cm 150kg 3 adjustable brackets (minor assembly) The widest choice of heights and the lowest price. The only raiser we stock that goes to 15cm.
Etac Hi-Loo$199.95 6cm, 10cm 20–20.5 × 27cm 150kg 4 adjustable brackets, tool-free A roomier opening than the budget seats and the gentlest 6cm step-up. Swedish-made, very stable.
Derby Deluxe$345.95 5cm, 10cm 21.5–25.5 × 26cm 190kg Bracket and nut, tool-free The widest opening we sell (25.5cm on the 10cm model) and the highest weight rating. Choose this if reaching to wipe is the problem.
Toilet Seat Raiser with Armrests$139.95 7.5cm, 12.5cm 15 × 28cm 127kg Side + rear locking brackets The only raiser with arms to push up from. Best when standing up is harder than sitting down. Narrowest opening of the range.

Can’t reach to wipe? That’s an opening-size problem, not a height problem. The Derby Deluxe at 10cm has the widest opening we sell at 25.5cm across. If you’ve already had that trouble with a raiser, tell us before you order and we’ll point you at the right one.

Struggling to stand back up? Extra height alone often isn’t enough — you need something to push against. Either the raiser with armrests or an over-toilet frame will do more for you than a taller seat.

Print the measuring sheet

Please choose carefully. Raised toilet seats are a personal hygiene product, so we can’t take them back for change of mind or the wrong choice. Faulty items are always covered under the Consumer Guarantees Act. If there’s any doubt at all, ring Kellie on 022 022 9956 or send a photo of your toilet and your measurements — we’ll tell you which one to buy, or tell you honestly that a frame would suit you better. It costs you nothing and saves us both the hassle.

Compare products

{"one"=>"Select 2 or 3 items to compare", "other"=>"{{ count }} of 3 items selected"}

Select first item to compare

Select second item to compare

Select third item to compare

Compare