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Mattress topper sizes

Toppers follow standard mattress sizes. Thickness, and one maker's California king length, can differ.

Short answer: toppers are generally made in the six standard mattress sizes and can be anywhere from 1 to 4 inches thick.^{[1 · Nov 12, 2026]} One maker's 2 in memory foam topper is listed at twin 38 × 75 in, twin XL 38 × 80 in, full 54 × 75 in, queen 60 × 80 in, king 76 × 80 in and California king 72 × 83 in.² That California king is 1 in shorter than the usual 72 × 84 in California king mattress,^{[3 · Nov 12, 2026]} so check the listed length.

Standard mattress sizes a topper follows

A sleep-research guide says toppers are generally made in the six standard mattress sizes.^{[1 · Nov 12, 2026]} Those mattress sizes are:^{[3 · Nov 12, 2026]}

One maker's topper dimensions

Some toppers rest on the mattress; others use elastic straps to stay in place.^{[1 · Nov 12, 2026]} Buy the same size name as your mattress, then read the listed width, length and thickness.

Topper vs pad vs protector

A topper is a more substantial layer meant to change how firm the mattress feels, typically 1 to 4 in thick, and is not usually meant to keep liquids off the mattress.^{[1 · Nov 12, 2026]} A mattress pad is usually 1 to 2 in thick at most and may add a little plushness or help shield the bed.^{[1 · Nov 12, 2026]} For a thin waterproof layer, see mattress protector sizes. A topper adds height, so measure the mattress and topper together when you buy sheets.

Need the underlying bed size first? See the mattress size chart.

Sources: 1. Sleep Foundation, Mattress pad vs. mattress topper. 2. Layla Sleep help, What are the dimensions of the topper?. 3. Sleep Foundation, Mattress sizes and dimensions guide. 4. NIST, SI units: length. Checked Nov 12, 2026. Trademarks belong to their owners; figures are restated in our own words and tables, not reproduced.