🧒 Bed Sizes by Age: The Complete Guide for Kids (US + Global Insights)

Choosing the right bed size for your child isn’t just about age—it’s about safety, space, sleep quality, and future-proofing. From cribs to teen beds, here’s a comprehensive guide to the best bed sizes by age, including how these standards vary around the world.

👶 0–2 Years: Crib Beds

US Size	69×132 cm (27×52 in)
Best For	Newborns to age 2
Also Called	Standard crib mattress
Mattress Depth	10–15 cm (4–6 in)

✅ Pro Tips:

Crib mattresses must be firm and snug-fitting (no gaps!).
Stick with a tight fitted sheet only—no pillows or quilts.

🌎 Alternatives by Region:

UK/EU: Common crib size is 60×120 cm (23.5×47 in)
Asia: Japan’s cribs often use 60×90 cm (23.5×35.5 in)
Australia: Similar to US (69×130 cm is standard)

👼🏻 2–5 Years: Toddler Beds

US Size	Same as crib (69×132 cm / 27×52 in)
Best For	Ages 2–5, transitioning from crib
Frame Type	Low to ground, side rails included

✅ Pro Tips:

A toddler bed uses the same mattress as a crib—only the frame changes.
Great transitional solution before committing to a bigger bed.

🧸 Fun Fact: Many toddler beds are themed—princess castles, race cars, dinosaurs—you name it.

🌎 Global Note:
In the UK, some families skip toddler beds entirely and move straight to a small single (75×190 cm / 30×75 in).

🧒 4–7 Years: Small Single or Junior Beds

US Equivalent	Not standardized; often 75×165 cm (30×65 in) or custom
Best For	Preschoolers, small kids who’ve outgrown toddler beds
Frame Height	Still low, with or without guardrails

✅ Pro Tips:

Great for compact rooms or bunk beds.
These are less common in the US, but popular in Europe and Asia.

🌎 Alternatives:

UK: 75×175 cm (30×69 in) “Small Single”
EU: 80×180 cm (31×71 in) or 70×160 cm (28×63 in)
Japan: Compact, often custom-sized junior beds
Australia: Small singles exist, but most transition directly to regular Singles

👧 6–12 Years: Twin / Single Beds

US Size (Twin)	99×190 cm (39×75 in)
Best For	School-age kids, bunk beds
Also Called	Single bed

✅ Pro Tips:

Twin is the most common size for kids after age 5 in the US.
Works great for bunk beds, trundle beds, and daybeds.

🛏️ Quirk: Twin beds are still referred to as “single beds” in the UK, EU, and Australia.

🌎 Global Match:

UK/Asia/EU: Single = 90×190 cm (35×75 in)
AU: Single = 92×188 cm (36×74 in)

📏 10+ Years: Twin XL or Full for Tweens & Teens

🟦 Twin XL

Size	99×203 cm (39×80 in)
Best For	Tall tweens, early teens

✅ Pro Tips:

Adds 5 extra inches in length—ideal for growing kids.
Standard size in college dorms (makes it future-proof).

🟪 Full (Double)

Size	137×190 cm (54×75 in)
Best For	Teenagers, solo sleepers who need room. Room for two teenagers when friends visiting.

✅ Pro Tips:

Full beds allow room to sprawl—and future guests too.
Some families skip Twin entirely and go straight to Full.

🌎 Global Alternatives:

UK Double: 135×190 cm (53×75 in)
EU Double: 140×200 cm (55×79 in)
AU Double: 138×188 cm (54×74 in)

🧭 Bed Size-by-Age Summary Chart (US Focus)

Age Range	Recommended Size	Dimensions (cm/in)
0–2 yrs	Crib	69×132 cm (27×52 in)
2–5 yrs	Toddler (same mattress)	69×132 cm (27×52 in)
4–7 yrs	Junior / Small Single	~75×165 cm (30×65 in)
6–12 yrs	Twin	99×190 cm (39×75 in)
10–18 yrs	Twin XL or Full	99×203 cm (39×80 in) / 137×190 cm (54×75 in)

✅ Final Takeaways

Start small: crib → toddler → twin is the usual US path.
Twin XL is a smart long-term pick—especially for tall kids.
In Europe, Asia, and Australia, sizes are similar but labels vary—always check the measurements.
Guardrails, low bed height, and firm mattresses are key safety considerations through age 6–7.
If space allows, upgrading to Full by tween years can avoid another mattress swap during high school.