Kids bed and mattress sizes in New Zealand: a sizing guide

Getting the size right saves you buying twice. Here is how the sizes compare, which one suits which child and room, when it is worth sizing up, and how to match a mattress that supports a growing body.

The sizes, in centimetres

New Zealand bed sizes are standard, so a size is the same wherever you shop^[1]:

• Single, 91 x 188cm. Younger children, smaller and shared rooms.
• Long single, 91 x 203cm. Tall children who do not need extra width.
• King single, 107 x 203cm. The size that grows with them, into the teens.

Which size for which child and room

• A single is the classic first proper bed. It fits the most rooms, leaves floor space for play, and is the easiest to move and dress.
• A long single keeps the single’s slim width but adds length, which suits a tall child in a narrow room.
• A king single is the long game. Children grow faster than a good frame wears out, and the extra width earns its keep for bedtime stories, sick days and a child who sprawls. If the room takes it, it is often the size you only buy once.

In a shared room, a bunk or a trundle can be smarter than two separate frames, giving each child a proper bed without filling the floor. See our kids beds buying guide for how those compare.

When to size up

• Cot to single or king single: most children make this move between 18 months and three and a half years, guided by readiness rather than age alone^[2].
• Single to king single: if you started with a single, a growth spurt, a child who runs out of length, or the shift into the teens is the usual prompt to go up to a king single.

The mattress: support beats plushness

The frame holds the size; the mattress does the real work for a growing spine. Children need firmer support than adults, so a mattress that feels luxuriously soft to you can leave a small body poorly aligned night after night^[3]. As a rough guide:

• Toddlers and young children (about 2 to 5): a firm to medium firm feel gives a small, light body the support it needs^[3].
• School age children (about 6 to 12): medium firm works well for most^[3].
• Avoid a very soft, sink-in feel, especially for younger children^[3].

A few New Zealand practicalities: buy for the next four to five years rather than this year’s height, choose a breathable cover because our humidity swings between seasons, and look for a washable or removable cover for the younger years and foam certified to a recognised low emission standard such as CertiPUR-US (with OEKO-TEX for the fabric)^[3]. Dreamland mattresses are made in single and king single sizes (among the larger sizes too), so you can match the mattress to a kids frame and try the feel in person.

One extra rule for bunks

If the bed is a bunk, mattress depth matters for safety, not just comfort. The mattress must not be so thick that it lifts the sleeping surface too close to the top of the guardrail, which would reduce the fall protection the guardrail is there to give. Check the maximum mattress depth for the bunk, and keep the guardrail standing well proud of the mattress top. Our bunk bed safety checklist covers this.

Timber or upholstered

Dreamland’s kids frames come in two families. The timber range is the durable, classic choice: Daisy and Jack are king single frames, and Charlie and Tyler come as frames and as bunks, with the Charlie and Tyler bunks built and tested to the AS/NZS 4220 safety standard. The newer upholstered king singles, Theo in blue and Mila in soft pink, offer a softer, quieter look for a single bed; they are frames, not bunks.

The short version

• Kids sizes: single 91 x 188cm, long single 91 x 203cm, king single 107 x 203cm.
• A single suits young children and small rooms; a king single grows with them into the teens.
• Match a medium firm mattress (firm to medium firm for the youngest) and buy for the next few years.
• On a bunk, watch the mattress depth so the guardrail still stands well above the sleeping surface.

Browse the kids beds and bunks range or find your nearest stockist to see the sizes in person.