Sleep advice · Measuring guide
Measuring your mattress,
step by step.
Choose your shape and follow the steps. Measure the base the mattress will sit on, not your old mattress. Prefer to be sure? In your campervan, caravan or boat, we come and measure for free.
01Before you start
Four golden rules.
- 01
A steel tape measure
A rigid tape measure stays straight; a fabric tape stretches.
- 02
Measure the base
Not your old mattress: it has often sagged or shrunk.
- 03
Measure twice
In two places, everything in centimetres. If in doubt, note both measurements.
- 04
Photo with tape measure
A photo from above with the tape measure in shot is worth a thousand words.
02Per shape
Choose your shape.
And measure step by step.
The letters are the same as in the configurator: A is the width, B the length, C the bevel and R the radius of a curve. For a boat mattress, A is the straight side, B the width at the bottom, C the outer side and D the angled side.
Rectangular mattress
- A, width: measure from edge to edge, at both the head and the foot end. If the mattress sits in a frame or box, note the smallest measurement.
- B, length: measure from the head end to the foot end, on both the left and the right.
- Check: also measure the two diagonals. If they’re equal, your base is nicely square.
French-style mattress with one bevelled corner
- A and B: measure the full width and length, as if the bevelled corner weren’t there.
- C: measure from the (imaginary) corner point along the edge to where the bevel begins. At 45°, it’s the same length on both sides.
- Is C different on each side? Note both measurements in your message or add a photo.
- Left or right: right means the bevelled corner is on your right-hand side when you’re lying in bed.
French-style mattress with two bevelled corners
- A and B: measure the full width and length, up to the imaginary corners.
- C: at one corner, measure along the edge how far it is bevelled. In the configurator, C is the same at both corners (45°).
- Are the two corners different? Give both measurements in your message or add a photo.
Mattress with a rounded corner
- A and B: measure the full width and length, up to the imaginary corner point.
- R: measure along the edge from that corner point to where the curve begins.
- Left or right: right means the rounded corner is on your right-hand side when you’re lying in bed.
Mattress with a rounded end
- A: measure the width at the widest point. B: measure the length through the middle, to the furthest point of the curve.
- R: the radius of the curve across the full width. The larger R, the flatter the arc; if the foot end is a semicircle, R is half of A.
- Don’t know R? Also measure the length along the side, up to where the curve begins, and put it in your message or add a photo.
Made-to-measure foam without a cover
- A: measure the width at the widest point. B: measure the length from end to end, through the middle.
- The ends are semicircular: the radius is half of A. If your shape is different, choose ‘Mattress in a special shape’ and add a photo.
Boat mattress port side
- A: measure the length of the straight side, from the point (at the front) to the back. B: measure the width at the bottom, at the back.
- C: measure the outer side, from the bottom rear corner to the bend. D: measure the angled side, from that bend to the point.
- Port: the piece on the left when you look forward, towards the bow. The straight side is in the middle, the bend against the hull.
- Does the hull slope or curve outwards? Measure at the height where the top of the mattress will be and mention it in your message.
Boat mattress starboard side
- A: measure the length of the straight side, from the point (at the front) to the back. B: measure the width at the bottom, at the back.
- C: measure the outer side, from the bottom rear corner to the bend. D: measure the angled side, from that bend to the point.
- Starboard: the piece on the right when you look forward, towards the bow. The straight side is in the middle, the bend against the hull.
- Does the hull slope or curve outwards? Measure at the height where the top of the mattress will be and mention it in your message.
Two-part trapezium, port and starboard
- A: measure the length of the straight side of one piece, from the point (at the front) to the back. B: measure the total width at the bottom, across both pieces together.
- C: measure the outer side of one piece, from the bottom rear corner to the bend. D: measure the angled side, from that bend to the point.
- We make two mirror-image pieces, split down the middle: one on the port side and one on the starboard side.
- Does the hull slope or curve outwards? Measure at the height where the top of the mattress will be and mention it in your message.
Round mattress
- A, diameter: lay the tape measure across the middle. Slide it back and forth a little: the largest measurement is the diameter.
- Measure in two or three places, a quarter turn further each time. If the measurements differ, the shape isn’t perfectly round: mention it in your message.
Mattress in a special shape
- Lay a large sheet of paper or cardboard on the base and trace the outline. A sketch on paper with the measurements added works too.
- Measure the largest width and length, plus a few measurements in between.
- Take a photo from above with the tape measure in shot and add it in the configurator. No need to post anything.
03Tips per bed
Campervan, boat or round bed.
Campervan & caravan
- Measure the base or board the mattress sits on, not the old cushions.
- Watch out for wheel arches, doors and cupboards that need to be able to open.
- Note how much space there is above the bed: that helps when choosing the thickness.
Boat & yacht
- Measure at the height where the top of the mattress will be: the hull often slopes.
- For each piece, measure A (straight side), B (width at the bottom), C (outer side) and D (angled side). Note whether the piece is on the port side, the starboard side or both (V-berth, two-part).
- Watch out for hatches and lockers under the berth that need to stay accessible.
Round bed & special shape
- Measure the inside of the bed frame, in several places through the middle.
- For an unusual shape: trace the outline on paper or cardboard and photograph it with the tape measure in shot.
Would you rather we did it for you? In your campervan, caravan or boat, we come and measure for free. Book a free measuring appointment
04Measuring sheet
Print, measure, photograph.
Tick your shape, fill in the measurements and send a photo of the sheet via the configurator or WhatsApp.
Measuring sheet for a made-to-measure mattress
Measurements in centimetres · measure the base, not your old mattress
Rectangular mattress
French-style mattress with one bevelled corner
French-style mattress with two bevelled corners
Mattress with a rounded corner
Mattress with a rounded end
Made-to-measure foam without a cover
Boat mattress port side
Boat mattress starboard side
Two-part trapezium, port and starboard
Round mattress
Mattress in a special shape
SleepOutlet Middelkerke · Rietstraat 8, 8430 Middelkerke · +32 475 34 97 05 (also WhatsApp) · sleepoutletmiddelkerke.be
Questions · Measuring
Good to know.
Question 01How do I measure my mattress?
Measure the base the mattress will lie on, not your old mattress. Note everything in centimetres: A is the width at the widest point, B the length from head end to foot end. For a bevelled corner, also measure C: how far the corner is bevelled along the edge.
Question 02What is C for a bevelled corner?
C is how far the corner is bevelled along the edge, measured from the imaginary corner point. In the configurator, the bevel is the same length on both sides (45°); if yours is different, give both measurements.
Question 03What is R for a rounded corner?
R is the radius of the curve. Measure along the edge from the imaginary corner point to where the curve begins. If the foot end is a single semicircle, R is half the width.
Question 04Do I need to send a cardboard template?
No, you don’t need to send anything in. Add a photo or drawing with your measurements in the configurator, or send them via WhatsApp. If anything is unclear, we’ll get in touch. In a campervan, caravan or boat, we come and measure for free.
Question 05Do you come and measure in my campervan or boat?
Yes. We come and measure for free in your campervan, caravan or boat. That way your new mattress fits perfectly, right into every corner.
Prefer to talk it through first?
Sadik helps you personally, in the showroom, on the phone or via WhatsApp.