Quick Answer
Full (54×75") is the recommended size. For a single adult who wants more sleeping width than a Twin, in a room 10x10' or larger, or for a guest room that occasionally hosts couples. Our top pick is the Nectar Classic Memory Foam at ~$499, with a 365-night trial and Forever warranty.
The Full (also called Double) measures 54x75 inches, giving a single adult 54 inches of personal width compared to a Twin's 38 inches. That extra 16 inches means room to stretch, roll over, and share the bed with a pet. It fits rooms 10x10' and up with nightstands on both sides. The Nectar Classic is the top pick: its medium-firm memory foam prevents the sinking that lighter adults often feel on softer mattresses, and the 365-night trial lets you test it far longer than the typical 100-night window. For guest rooms, a Full accommodates visiting couples in a pinch while costing significantly less than a Queen.
Dimensions
54" × 75"
Min Room Size
10' × 10'
Frame Size
58" × 81"
Best For
Single adults who want space, guest rooms
~$499
Top-rated Amazon mattress with a 365-night trial and forever warranty. Medium-firm memory foam that works for every sleep position.
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