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- Nursery Articles -

Toddler Mattress Size Guide

+ When To Make the Switch

Emerson 4-in-1 Toddler Bed Conversion Kit

Is your little one outgrowing their crib? It might be time to transition to a toddler bed.

This guide gives you the details on toddler bed dimensions and mattress size. You'll also find tips on how and when to make the switch. With a smoother transition, everyone in the family will rest easier.

Larkin 4-in-1 Convertible Crib

What is the standard toddler mattress size?

The standard toddler mattress size is the same as a crib mattress: 27 ¼ inches x 51 ⅝ inches. Many cribs—often called convertible cribs—turn into toddler beds using the same mattress. Some even convert into a twin bed or daybed as well.

Toddler bed dimensions can vary if you're using a non-standard crib. With those models, a corresponding mattress should come with the crib. These non-standard toddler beds range from 27 ¼ - 31 inches wide and 51 ⅝ - 71 inches long. Be sure to use the mattress that comes with the bed so you know that it fits properly.

Crib Mattress vs. Toddler Mattress

In most cases, a crib mattress is the same as a toddler mattress size, as the crib converts into a toddler bed. With convertible cribs, you might remove a side rail or lower it to turn it into a toddler bed. Your child will sleep on the same mattress.

If you buy a toddler-specific bed, the mattress should come with it. If you try a different mattress in a toddler-specific bed, it could cause gaps between the sides of the crib and the mattress—posing an entrapment or suffocation risk. In general, you shouldn’t have more than an inch—or two-fingers width—between the mattress and sides at any point.

Shelter Toddler Bed

Crib Mattress Conversion Tips

When converting your crib to a toddler bed, there are a few things that will make it the safest, comfiest spot for your little one.

Follow assembly instructions: Above all else, follow the instructions provided by your specific crib make and model. Don’t skip over certain steps or guess at how to construct it.

Ensure you have all the pieces: If there are broken or missing pieces, don’t use the bed as it could be a safety hazard. You're better off finding a different crib or toddler bed.

Check to make sure it's sturdy: Your toddler probably wiggles and rolls throughout the night. Make sure the frame is strong enough to hold up to toddler treatment. 

Keep it low to the ground: Your toddler shouldn’t be far off the ground in case they fall. A lower clearance also makes it easier for them to get in and out of bed by themselves. 

Secure the side rails: Prevent falls out of bed by making sure your model has rails, even half-rails. There shouldn’t be any gap between the rail and the side of the bed frame.

Double-check your child-proofing: In case your toddler finds their way out of bed, be sure the room is safe for them to roam. That includes covering electrical outlets, ensuring there are no small items for them to swallow and no windows they could crawl out of. If they’re tall enough to open the door, be sure any stairs are blocked with a gate. Keep medicines out of their room or up high enough so they cannot reach them. 

west elm x pbk Safari Baby Bedding

When is it time to transition to a toddler bed?

It’s time to transition to a toddler bed when your child reaches three feet in height, begins climbing out of their crib, or is between 18 and 24 months. If they reach one of these milestones, consider making the switch. For example, if your toddler can stand up and swing a leg over the rail, you risk them falling out.

You might also decide to transition beds if another baby is joining the family and needs the crib or you're moving and it makes sense to rebuild the crib as a toddler bed.

Your mattress should be six inches or less in depth. Mattresses with coil springs usually measure between five and six inches while foam mattresses tend to be between four and six inches deep. Choose the depth and material that feels most comfortable to you. If it's a mattress you'd sleep on, chances are your little one will too.

If you feel your child is old enough for a big bed and the newfound freedom of being able to get out of bed, then it’s time. More than anything, keep the safety of your little one in mind.

Tips for a smoother transition to a toddler bed

Like any change for your child, there are a few ways to make it easier on them—and you.

Plan the timing: The transition to a toddler bed shouldn't come when your child has other changes going on because it makes it more overwhelming for them. For example, if they recently started at a new daycare or welcomed a new sibling to the family, try to stagger the transitions. It's easier for children to process one new experience at a time.

Talk with them about it: Explain to your little one that they’re upgrading to a toddler bed because they're bigger and older. Tell them about their new bed, show it to them, and discuss any new responsibilities. If you’re using a convertible crib, explain to them that it’s their same bed but as the “big kid” version. 

Share a story: If you or your library has a book about toddler beds, read it to them during the transition period. They'll be more comfortable with the idea. It might even make them excited about the change. 

Do a trial run: Before they sleep a full night in their new toddler bed, have them take a nap in it with their favorite blanket first. This gives them a chance to practice and get used to it. When night time comes, they’ll be more familiar with their new sleeping arrangement.

Keep the same bedtime routine: If you usually cuddle and read a story before bed, maintain the tradition. Because the new bed will already be different, keep some continuity before they fall asleep. 

With a safe, comfortable toddler bed, your little one will have a cozy place to lay their head. As they grow into their toddler bed, they’ll become more comfortable with it, and you will too. Make their bed a personalized resting place with fun, playful sheets. They’ll be more excited to crawl in night after night.

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