🛏 Pillow Insert Size for Sham Calculator
Match sham width, height, fullness, and fill type to the right insert size
| Sham style | Typical width | Best shape | Fit note |
|---|---|---|---|
| 20x26 sham | 20-24 in | 16-18 sq | Soft curve |
| 20x20 sham | 22-28 in | +2-3 in | Tucks in |
| Rectangle sham | 24-30 in | 18-20 sq | Wide seat |
| Lumbar sham | 22-26 in | size up | Deep sit |
| Standard size | Metric size | Best use | Fit note |
|---|---|---|---|
| 18x18 | 46 cm | Petite | Small shams |
| 18 sq | 46 cm | Balanced | Euro sham |
| 20 sq | 51 cm | 26x26 | Bigger seats |
| +2-3 in | 30x51 | Lumbar | Narrow backs |
| Sham | Insert | Look | Use |
|---|---|---|---|
| 18x18 | 20x20 | Soft | Relaxed |
| 20x20 | 22x22 | Tailored | Crisp |
| 20x26 | 22x28 | Plush | Long line |
| 26x26 | 28x28 | Luxe | Layered |
| Fill | Hold | Best use | Note |
|---|---|---|---|
| Down | 55-70% | Soft | Simple |
| Blend | 65-85% | Balanced | Layered |
| Poly | 80-95% | Full | Plush |
| Pair | 2 x 16 | Balanced | Layered |
Choosing the right size of pillow insert is a tiny detail that even so has a big influence on the look and feel of the pillow. Pillow inserts should be 1-2 inches bigger than the cover. Here is a universal rule for decorating.
For decorative pillow covers under 18 inches, choose a pillow insert 1 inch bigger. For covers of 18 inches or more, use a 2-inch difference. For instance, for an 18×18 cover use a 20×20 pillow insert, while for a 20×20 cover you take a 22×22 pillow insert.
How to Choose the Right Pillow Insert Size
For big square covers between 22×22 and 24×24 you must add 2-3 inches. For a 22×22 cover goes a 24×24 pillow insert. If you want a firmer and full pillow, buy a pillow insert one size bigger than the cover, for example 18×18 pillow insert works for a 17×17 cover.
Too slim pillow insert makes the cover sagy. Making a cover a bit smaller than the pillow insert stays puffy and holds shape better. The pillow insert should be an inch bigger than the cover, otherwise the pillow will seem empty and flat.
Lumbar pillow covers work different. For lumbar, a pillow insert of the same size as the cover avoids overstuffing. For a 12×20 lumbar cover use a 13×21 or 14×22 pillow insert.
Smaller lumbar follow the same: 8×24 cover with 8×26 pillow insert, 10×20 cover with 10×22 pillow insert.
One thing to note: a tight case compresses everything and makes the pillow hard and rigid. That is not good. For shams 18×18 and bigger use a pillow insert 2 inches bigger than the sham.
Smaller shams under 18×18 take the same size or 1 inch bigger for a fuller look.
Occasionally shams seem droopy. Denser pillow inserts help them keep their shape. A pillow insert too little for the cover makes it flat after putting it on.
Even two pillow inserts in one cover can give a full look.
To measure a pillow cover, lay the empty cover on a flat surface and pull the seam tightly against the tape measure. A pillow cover is basically two rectangles of fabric sewn together. Measure along the long and short edge, pulling straight to get the final dimensions.
Not always necessary to change pillows themselves. Throw pillows with pillow inserts are a good way to refresh the room. Simply choose the right size and shape, or consider materials if that is most important.
Square and lumbar pillow inserts sell separately from covers, so remember that whenshopping.
