How to Properly Measure Foam Cushions: A Step-by-Step Guide

 

Whether you're replacing worn-out cushions, upgrading your seating, or ordering custom-cut foam, getting accurate measurements is crucial. Foam cushions must fit snugly inside their covers or frames to ensure comfort, durability, and a professional finish.

Here’s a simple step-by-step guide to help you measure your foam cushions correctly — whether for a sofa, chair, bench, or any other application.

📏 What You’ll Need:

  • A firm tape measure or ruler
  • A flat surface
  • Pen and paper (or phone) to record measurements

The cushion cover or original foam (if available)

Step 1: Measure the Length

Lay the cushion cover or foam on a flat surface. Measure the longest side from end to end. This is your length.

Tip: If you’re measuring a cushion cover, pull it taut but don’t stretch the fabric.

Step 2: Measure the Width

Next, measure the side running perpendicular to the length — this is the width of the cushion.

Make sure to measure edge to edge, at the widest points.

Step 3: Measure the Thickness (Height)

Stand the foam upright or look at the side edge of the cushion cover to measure the thickness, also known as the height.

Most standard seat cushions range from 2" to 6" thick, depending on use and comfort level.

Step 4: Account for Curves or Shapes

If your cushion has rounded corners, tapered edges, or unique contours:

  • Trace the shape onto paper or cardboard and send it to your foam supplier.
  • Alternatively, check if your supplier accepts templates or offers custom shaping based on your outline.

Tip: Always provide the widest dimensions — it's easier to trim foam down than to fix a piece that's too small.

Step 5: Add Compression (Optional but Recommended)

If the foam will go inside a fabric cover, you may want to add 1–2 cm (around ½–¾ inch) to the thickness to ensure a snug, full fit once the foam is inserted. This is known as compression or "overstuffing" and helps avoid saggy cushions.

Pro Tips:

  • Always double-check your measurements before ordering.#
  • If you’re replacing old foam, don’t rely solely on the worn piece.
  • Measure the cushion cover, not the compressed foam.
  • When in doubt, contact your supplier — many offer advice or even free measuring support.

Conclusion

Measuring foam cushions properly takes just a few minutes, but it makes all the difference in getting a comfortable, well-fitted result. Whether you're ordering new foam for a DIY project or replacing cushions for a beloved piece of furniture, accuracy is key.

At Foam Seating, we offer a custom foam calculator to make ordering simple—just enter your length, width, and height, and we’ll do the rest. If you need help with measurements, don’t hesitate to reach out!


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