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Mattress Size Guide

Dimensions from Twin to California King, with simple fit tips for rooms, sleepers, and budgets.

Size guide

Mattress Sizes Explained

Compare the key differences between common mattress sizes, including who each size fits, pros and cons, and typical room fit guidance.

Twin mattress size (38" x 75")

Small-room friendly and budget-conscious, a Twin mattress gives kids and solo sleepers a cozy sleep surface without crowding the room.

  • Space‑saving Twin mattress fits small bedrooms and bunk beds without crowding the room.
  • Affordable bedding and accessories are easy to find in Twin size.
  • Comfortable for kids and most sleepers up to about 6 feet tall.
  • Lightweight and easy to move through tight hallways and stairs.
  • Too narrow for two; consider a Full mattress if sharing or for growing teens.
38"75"

Twin XL mattress size (38" x 80")

A Twin XL mattress adds 5 inches of legroom for taller sleepers and dorm rooms—extra length without taking more floor space.

  • Twin XL mattress adds 5 inches of legroom so feet stay comfortably on the bed.
  • Same slim width as Twin fits narrow rooms and bunk frames.
  • Dorm‑ready: Twin XL sheets and accessories are widely available.
  • Two Twin XLs combine later to create a Split King for couples.
  • Requires Twin XL bedding; confirm fitted‑sheet depth for campus beds.
38"80"

Full mattress size (54" x 75")

A Full mattress adds valuable width for solo adults while still fitting compact bedrooms—a practical upgrade over Twin sizes.

  • Full mattress gives solo adults extra shoulder room compared to Twin sizes.
  • Fits many 10×10 ft rooms while leaving comfortable walking space.
  • Usually costs less than a comparable Queen mattress.
  • Works well for guest rooms; can accommodate two occasionally.
  • Tight for couples long‑term; upgrade to a Queen for more width.
54"75"

Queen mattress size (60" x 80")

The Queen mattress is the go‑to choice for most couples—roomy without overwhelming typical primary bedrooms.

  • Queen mattress is the most popular choice for couples—roomy without dominating the space.
  • Balances sleeping surface and furniture layout in 10×10 ft rooms.
  • Deep selection of bedding, bed frames, and accessories for easy shopping.
  • Great for combination sleepers who need shoulder and hip room.
  • If you want extra elbow room or co‑sleep with pets, consider a King.
60"80"

King mattress size (76" x 80")

A King mattress maximizes shared sleep space—great for couples, pets, and sprawling sleepers in wider rooms.

  • King mattress offers maximum width—ample personal space for each partner.
  • Comfortable if kids or pets join you at night.
  • Two‑piece foundations or split bases simplify delivery in tight stairways.
  • Best fit in rooms around 12×12 ft or larger with nightstands.
  • Measure doorways, hallways, and stairs; the large footprint needs planning.
76"80"

Split King mattress size (76" x 80")

Split King pairs two Twin XL mattresses so partners can personalize firmness and adjust independently—comfort without compromise.

  • Split King mattress uses two Twin XL pieces so partners choose their own firmness.
  • Ideal for adjustable bases—independent head and foot movement on each side.
  • Excellent motion isolation between sides for light sleepers.
  • Easier to move through tight spaces than a one‑piece King.
  • Bedding can cost more; a king‑size topper helps bridge the center seam.
76"80"

California King mattress size (72" x 84")

California King extends the length for taller bodies while keeping a slightly slimmer width—made for long, narrow rooms.

  • California King mattress adds extra length (84") for taller sleepers.
  • Slightly narrower width suits long, narrow rooms where space is tight.
  • Popular with adjustable and platform frames for a modern look.
  • Plenty of legroom for couples and pets at the foot of the bed.
  • Fewer bedding choices than a standard King; confirm availability and lead times.
72"84"

Mattress Size Comparison Chart

Quickly compare width, length, and total surface area.

Comparison of mattress sizes
SizeWidth (in)Length (in)Area (sq in)
Twin38752850
Twin XL38803040
Full54754050
Queen60804800
King76806080
Split King76806080
California King72846048

How to Measure a Mattress and Your Room

Use this quick method to confirm the size you need and ensure your room layout works before delivery.

Measure the mattress

  • Length: measure from head to foot at the longest point.
  • Width: measure from side to side at the widest point.
  • Height: measure from the base to the top surface without pressing the cover.

Measure the room path

  • Doorways and hallways: measure clear width and height; remove doors if needed.
  • Stairs: measure stair width and landing depth; check ceiling height over stairs.
  • Layout: allow ~24–30" walking space around the bed wherever possible.
Brands may vary slightly from these dimensions. Always confirm the manufacturer spec sheet for exact measurements.

Standard Mattress Dimensions (Twin to California King)

Use these standard dimensions as a starting point. Brands may vary slightly, so confirm specifications before you buy.

Twin

38" x 75"

Compact and easy to place—great for kids' rooms, bunks, and small guest spaces.

38"75"

Best for

  • Kids
  • Small guest rooms

Note: Small footprint; budget friendly. Minimum room size: 7' x 10'.

Key points

  • Space‑saving Twin mattress fits small bedrooms and bunk beds without crowding the room.
  • Affordable bedding and accessories are easy to find in Twin size.
  • Comfortable for kids and most sleepers up to about 6 feet tall.
  • Lightweight and easy to move through tight hallways and stairs.

Too narrow for two; consider a Full mattress if sharing or for growing teens.

Twin XL

38" x 80"

Extra length without extra width—popular in dorms and teen rooms.

38"80"

Best for

  • Taller sleepers
  • Dorms

Note: Adds 5 inches of length. Minimum room size: 7' x 10'.

Key points

  • Twin XL mattress adds 5 inches of legroom so feet stay comfortably on the bed.
  • Same slim width as Twin fits narrow rooms and bunk frames.
  • Dorm‑ready: Twin XL sheets and accessories are widely available.
  • Two Twin XLs combine later to create a Split King for couples.

Requires Twin XL bedding; confirm fitted‑sheet depth for campus beds.

Full

54" x 75"

A practical upgrade over Twin sizes for single adults.

54"75"

Best for

  • Solo sleepers
  • Tight primary rooms

Note: More width than Twin. Minimum room size: 10' x 10'.

Key points

  • Full mattress gives solo adults extra shoulder room compared to Twin sizes.
  • Fits many 10×10 ft rooms while leaving comfortable walking space.
  • Usually costs less than a comparable Queen mattress.
  • Works well for guest rooms; can accommodate two occasionally.

Tight for couples long‑term; upgrade to a Queen for more width.

Queen

60" x 80"

Balanced space for couples without overwhelming the room.

60"80"

Best for

  • Most couples
  • Primary bedrooms

Note: Most popular size. Minimum room size: 10' x 10'.

Key points

  • Queen mattress is the most popular choice for couples—roomy without dominating the space.
  • Balances sleeping surface and furniture layout in 10×10 ft rooms.
  • Deep selection of bedding, bed frames, and accessories for easy shopping.
  • Great for combination sleepers who need shoulder and hip room.

If you want extra elbow room or co‑sleep with pets, consider a King.

King

76" x 80"

Largest standard width for ultimate elbow room.

76"80"

Best for

  • Couples
  • Pets or kids joining

Note: Maximum width. Minimum room size: 12' x 12'.

Key points

  • King mattress offers maximum width—ample personal space for each partner.
  • Comfortable if kids or pets join you at night.
  • Two‑piece foundations or split bases simplify delivery in tight stairways.
  • Best fit in rooms around 12×12 ft or larger with nightstands.

Measure doorways, hallways, and stairs; the large footprint needs planning.

Split King

76" x 80"

Two Twin XL pieces combine for a king-size sleep surface.

76"80"

Best for

  • Couples with different needs
  • Adjustable bases

Note: Two Twin XL pieces (38″ x 80″ each). Minimum room size: 12' x 12'.

Key points

  • Split King mattress uses two Twin XL pieces so partners choose their own firmness.
  • Ideal for adjustable bases—independent head and foot movement on each side.
  • Excellent motion isolation between sides for light sleepers.
  • Easier to move through tight spaces than a one‑piece King.

Bedding can cost more; a king‑size topper helps bridge the center seam.

California King

72" x 84"

Longer than a standard King and slightly narrower—great for tall sleepers.

72"84"

Best for

  • Taller couples
  • Long narrow rooms

Note: Extra length; slightly narrower. Minimum room size: 12' x 12'.

Key points

  • California King mattress adds extra length (84") for taller sleepers.
  • Slightly narrower width suits long, narrow rooms where space is tight.
  • Popular with adjustable and platform frames for a modern look.
  • Plenty of legroom for couples and pets at the foot of the bed.

Fewer bedding choices than a standard King; confirm availability and lead times.

Room fit tips

  • Leave about 24–30 inches of walking space around the bed where possible.
  • Consider door swing, closets, and dresser placement.
  • For adjustable bases, check stairwells and tight turns.
  • Measure elevator or hallway clearance in apartments.