How to Cut a Mattress Like a Pro: Step-by-Step Guide


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how to cut a mattress

Maybe you want to salvage your king size mattress by cutting it into two single size mattresses, or perhaps you want to make a futon out of your old mattress. Maybe you want to fit your mattress in an RV and need it in a custom dimension, or you’re simply downsizing and need to cut your mattress in half.

No matter the reason, it’s possible to cut your mattress with the RIGHT tools at home in no time.

What type of mattresses can be cut?

While you can cut all types of mattresses, it does not make sense to cut innerspring mattresses. Cutting through the metal coils of an innerspring mattress is a long, tedious process. So if you’re planning to cut an innerspring mattress, we feel it’s not worth the hassle. You’re better off disposing it of or donating it if it’s in a usable condition.

On the other hand, foam mattresses like memory foamlatex or general foam are easy to cut. Pocket spring mattresses can also be cut, but it requires a bit more effort.

Choosing the right cutting tool: Electric vs manual.

You can very much cut your mattress using a general-purpose kitchen knife or box cutter and a scissor, but it would be time-consuming, require elbow grease, and the cut would not even end up clean or straight.

Alternatively, you can invest in a decent electric knife or hot knife (both costing about $20), which will make the job a lot easier, and later you can use them for other purposes.

Both are good options, and it comes down to personal preference. We recommend using an electric knife because it’s easy to handle, makes straight cuts and is not too expensive.

electric knife vs knife

How to cut your mattress - Desired size or half.

Follow these simple steps: whether you want to cut your mattress in half or any custom dimensions.

Equipment required:

  • [Paid options] Electric carving knife, electric bread knife, hot knife, box cutter or hand saw.
  • [Common household items] Utility knife or serrated bread knife.
  • Dressmakers shears or a sharp scissor to cut the mattress cover if it’s not removable.
  • Measuring tape or a ruler to measure dimensions.
  • Pencil or marker to mark the cutting line.
  • [Optional] Seam ripper to open the mattress cover seam. Only required if you want to save the mattress cover.
  • [Optional] T-square or any straight edge plywood or cardboard for a precise straight cut.
  • [Optional] Sewing kit and thread to re-stitch the mattress cover. You can also use a staple gun or a glue gun to stick the fabric together (not the best fix, though).


How to Cut Memory Foam, Latex or All-foam mattresses.

Step 1: Place the mattress on a firm surface like plywood or on a couple of cardboard sheets. While cutting the mattress, you wouldn’t want the knife to damage your bed frame or your flooring (if you’re cutting on the floor).

 Step 2: The next step is to remove the outer mattress cover. If the outer cover is removable, unzip it and set it aside. If the cover is not removable, you can either cut it along the seam using a seam ripper or cut it along one of the seams using a scissor. If you plan to re-use the cover, it’s best to cut carefully and along the seam.

Note: Never cut the mattress with the mattress cover on.

Step 3: Measure and mark the exact dimensions of the cut on the foam layer using a pencil or marker. To be precisely straight, measure the dimension from opposite ends along which the cut is being made and mark the straight line using straight edge plywood or cardboard.

For example, if you want to cut the mattress in half along the length, measure the middle point on both ends of the mattress (width-wise) and join the points using any straight edge to get a perfect straight line.

Step 4: Using a tool of your choice (electric or normal knife, bread knife, saw, box cutter etc.), start making light incisions along the marked line. Do not compress the foam while cutting, as it would make it more challenging to cut.

Make multiple passes of shallow cuts until you’ve cut through the entire thickness of the foam. Generally, the bottom layer is denser and harder to cut. Use a sawing motion while cutting and not a slicing one, as it will give you cleaner cuts. Remember to apply even pressure while cutting to get a clean straight cut.

If you’re using an electric knife, it’s best to make multiple passes instead of trying to cut through the entire thickness in one go as it might get stuck, and you might end up with an uneven cut.

Step 5Trim excess foam. Once you’ve cut through the entire thickness of the foam, remove any excess foam that’s hanging off the edge using a utility knife or scissor.

Step 6: Now, your mattress is cut into two pieces. Stitch the mattress cover back together using a sewing kit, glue it or wrap it in a fitted sheet and enjoy your new custom-sized mattress!

How to cut a pocket spring mattress.

pocket coil mattress inner core

The initial steps to cut pocket springs are the same as any foam mattress – place the mattress on a firm surface and remove the cover.

The difference is: Pocket spring mattresses have foam batting encasing the coils, unlike foam mattresses which are nothing but a large foam block. So you can’t simply saw through the mattress.

Depending on whether you want to reduce the dimension of any side or cut the mattress in half, follow the steps below.

Reducing dimension:

  1. Remove the seam or cut the corner of the side you want to reduce.
  2. Once the cover is removed, you will see the foam batting glued to the pocket coils.
  3. Carefully pull the foam batting, trying not to damage it.
  4. Next, you would see the independent pocket coils (springs) wrapped in fabric.
  5. Cut the fabric of each pocket coil and pluck the pocket spring out of the casing. 
  6. Do not pull the pocket coils as they may damage the upper comfort layer.
  7. Depending on how much you want to reduce the dimension, remove the required rows of pocket coils.
  8. Re-stitch or glue the mattress cover back on.

To cut the mattress in half:

  1. After removing the mattress cover, measure the centre point and mark it.
  2. Use a utility knife or box cutter to make a slit along the centre of the mattress until you hit the pocket coil layer. You should now be able to see the pocket coils running through the length of the mattress. 
  3. The rows of pocket coils are joined by fabric. Use a scissor to cut the fabric joints. Once all pocket joints along the centre are cut, use a knife to cut through the bottom foam layer. You’ve successfully cut the pocket spring mattress in half!

Word of warning: Cutting a pocket coil mattress in half may not make much sense as once the mattress is cut, the pocket coils could easily come loose without a foam batting encasing it.

Wrapping Up

That’s it! These are the steps on how to cut a mattress. We hope this guide was helpful. If you have any questions or suggestions, feel free to leave a comment below!

Happy mattress cutting! 🙂

Frequently Asked Questions (FAQs)

While you can cut a foam mattress like memory foam or latex horizontally, but you would need something like a horizontal band saw. A knife would be simply too small to cut the mattress horizontally, and cuts would be nowhere clean.

Cutting an innerspring or pocket spring mattress horizontally is a bad bad idea! Not only will the structure lose structural integrity rendering it unusable, but it would also require industrial equipment to cut the steel mass.

While you can cut an innerspring mattress, we wouldn’t recommend it. First, cutting through the metal coils requires a lot of work, and secondly, even after cutting, the end of the metal coils would protrude out, which can be pretty dangerous. It’s simply not worth all the effort.

That said, if you want to cut an innerspring mattress, you would need a bolt cutter or pliers to cut through the intertwined springs and a lot of time and patience.

Emma Bethany

Emma Bethany

Emma is a wellness writer who has shared her knowledge for over three years. Her Masters in Creative Writing for Therapeutic Purposes means Emma approaches each topic with compassion and gentle curiosity. She wants everyone to be as passionate about taking care of their body as she is. That’s why Emma believes investing in your sleep is an investment in yourself. She wants to create a loving space to learn self-care and build a beautiful bedtime routine to soothe the soul. She loves to discover new ways to enhance sleep and embraces a holistic lifestyle. She enjoys settling down in the evening with a good book and a cup of chamomile tea.


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