Save-Check

Bed Size Calculator

Full mattress in a 11×12 ft kids room

The short version

Tape a Full (54×75 in) in this 11×12 ft kids room: about 39" on each side and 69" at the foot. clears the 24" walk-space rule. Frames add extra width.

Living Context
180
335

Mattress Tip

Side sleepers need softer foam to relieve shoulder pressure points.

Recommended Bed

King

Dimensions

76"x80"

Best Firmness

Medium

Room PerspectiveGood Fit
Room Perspectives
76" Wide
80" Long
Fit

Walking Space

Perfect. You have ample space for nightstands and walking around the bed.

Future-Proofing

Even if you sleep solo, a Full or Queen offers much better resale value and versatility.

Numbers worth knowing

54×75 in

Full mattress

Source: US bedding

39"

Side clearance each way

Source: 24" walk-space rule

69"

Foot clearance

Source: 24" walk-space rule

Frequently Asked Questions

Does a Full fit a 11×12 ft kids room?
Yes, with ~39" side clearance and 69" at the foot versus a 24" walk-space floor. Nightstands eat more.
How much walk space should a mattress leave?
Plan at least 24 inches on any side you walk past so you can make the bed and open a nightstand drawer.
Do frames change this math?
Yes. Headboards, box springs, and platform rails add width. Tape the frame outline, not just the mattress spec.
Sources & Date
Published: 2026-09-29Last verified: 2026-09-29

References

Other published size checks