best bunk bed mattress

What Size Should My Kids' Mattress Be?

What Size Should My Kids' Mattress Be?

Key Takeaways:

  • Choose a mattress that matches both your bed frame size and its proper mattress height.
  • Mattress height is especially important for maintaining proper guardrail protection on bunk and loft beds.
  • Maxtrix offers 5", 8", and 10" mattresses to fit different beds, comfort preferences, and headspace needs.
  • Most trundle beds require a 5" mattress so they can slide smoothly beneath the main bed.
  • Maxtrix medium-firm, CertiPUR-US® certified memory foam mattresses provide supportive comfort and added peace of mind.

Finding Their Mattress Fit

Wondering how to choose the best mattress for your child? Mattress size is a natural place to start, but it’s not the only factor to consider. Height, firmness, and your bed type all play a role in finding the right fit. 

Maxtrix Kids is here to make the decision easier. In this guide, we’re sharing three key factors to consider when choosing a mattress that delivers comfort, safety, and lasting quality. 

White 8-inch gel memory foam mattress on light blue background, with textured surface and green label.
5-inch gel memory foam mattress with textured white cover for enhanced comfort.
Memory foam mattress with a textured white cover and gray fabric base.

Why Does Their Mattress Matter?

The right mattress supports a comfortable night’s sleep and, more importantly, your child’s growth. A proper fit and firmness help maintain healthy spinal alignment as they grow, so they can get the quality rest they need for school, sports, and everything in between. 

A well-fitting mattress is also essential for safety. If your child sleeps in a bunk or loft bed, the mattress's height helps maintain proper guardrail protection and create a secure, sleep-ready setup. 

3 Considerations When Purchasing a Mattress

1. Bed Size

First, make sure the mattress fits your bed frame. This is fairly straightforward. A twin-size mattress pairs with a twin bed, a full-size mattress with a full bed, and so forth.

Maxtrix offers kids’ mattresses and beds in sizes ranging from twin to queen. For a long-term setup that kids can grow into, consider a twin XL or queen-size bed frame and mattress. These setups are about 4.5 inches longer than standard twin and full-size beds, keeping up with the inevitable growth spurts we parents know and love.

2. Mattress Height

Mattress height, also known as mattress thickness, is another key factor to consider. On a single bed, a mattress that is too short may leave an awkward gap beneath the headboard, while one that is too tall can limit the amount of headboard available for sitting up, snuggling, and reading bedtime stories. 

To find the right fit, check the recommended mattress height in your bed’s product description. You can also measure from the top of the bed slats to the bottom of the headboard to determine how much mattress height the frame can accommodate. 

As for us, Maxtrix offers mattresses in three thicknesses: 5", 8", and 10". Each option delivers layered memory foam and supportive comfort. The best choice simply depends on your bed frame and preferred sleep setup. 

3. Mattress For Bunks and Lofts

For bunk beds and loft beds, mattress height goes hand in hand with safety. These beds rely on guardrails to keep your little sleeper secure as they dream big. A mattress with the correct thickness will provide plush comfort while leaving plenty of guardrail space.

For proper safety, the Consumer Product Safety Commission recommends that guardrails extend at least 5” above the mattress's top. The standard bunk bed and loft bed have 13” guardrails. With a mattress 5” to 8” tall, that leaves the 5-inch minimum. 

Don’t forget the bottom bunk! A well-fitting mattress leaves enough headspace for kids to sit up and enjoy lounging and relaxing at bedtime. Federal standards recommend at least 30” between the mattress and the top bunk.

Two stacked white Gel Memory Foam mattresses on a blue background.
Memory foam mattress with textured design for optimal comfort and support.
Memory foam mattress with textured white surface and visible brand tag, ideal for supportive and comfortable sleep.

Maxtrix Guardrails and Mattress Height

At Maxtrix, safety is our first, second, and third priority. 

Our solid wood bunks and lofts for kids feature industry-leading 16-inch guardrails, giving your family more flexibility and freedom when choosing a mattress height. Pick a 10” mattress for maximum coziness, a 5” for plenty of headroom, or find the perfect balance between the two with our 8” mattress. 

No matter your pick, our extra-tall guardrails are here to keep your sleeper secure as ever.

Mattresses For Trundles

Adding a trundle bed to the mix? Make sure you pick the right mattress height! The right fit allows the trundle to slide smoothly beneath the bed and tuck neatly away when not in use. 

The majority of trundle beds pair with a twin-size 5” mattress, but always measure or check your bed’s product details before choosing one. Maxtrix trundles are available in two sizes. Our standard trundle fits a Maxtrix-exclusive trundle mattress, while our XL trundle fits a standard twin-size, 5-inch mattress.

With the right mattress, your trundle stays easy to use, simple to store, and ready for sleepover guests.

5-inch gel memory foam mattress with textured white cover for enhanced comfort.
Wooden trundle bed frame with a natural finish for space-saving bedroom solutions.
5-inch Gel Memory Foam Mattress with Quilted Cover for Comfort and Support

Maxtrix Mattress Safety and Quality

Besides being the perfect fit for your bed, bunk, loft, or trundle, what else makes Maxtrix stand out?

Thoughtfully designed for safety, our mattresses check all the boxes for child comfort and parent peace of mind. Each medium-firm mattress features layered memory foam that gently cradles the body, helps maintain spinal alignment, and evenly distributes weight to reduce tossing and turning. The result? Better sleep, better support, better mornings, feeling rested and ready for the day.

And when it comes to safety, our mattresses are hypoallergenic and CertiPUR-US® certified. This means third-party tested for harmful chemicals and VOC’s, ensuring your child gets the clean, safe sleep setup they deserve. 

Additional Mattress Options

The magic of Maxtrix mattresses doesn't just stop there! For kiddos who struggle with sleeping hot, meet our cooling mattress! The cooling gel and perforated memory foam pull heat away from the body for cooler, more comfortable nights' sleep.

Additionally, we know kids are prone to mistakes; that's just life! Our waterproof mattress covers protect against spills and stains. This way, their mattresses stay protected, and Mom and Dad won't have to worry!

Finally, our mattress 2-packs are an easy solution to setting up shared sibling rooms or sleepover setups. Place the mattress duo on your bunk bed, bed-and-trundle combo, or two single beds. No matter your bedroom setup, we have the fix.

Summary

The best mattress for kids should fit their bed frame, support comfortable sleep, and work for their changing needs. From low-profile 5" mattresses to extra-plush 10" options, Maxtrix makes it easier to find the right balance of mattress height, headroom, and support. Always measure or review your bed’s product details before choosing a mattress, especially when shopping for a bunk, loft, or trundle bed.

Ready to complete their sleep setup? Explore our complete kids’ mattress collection and find the right fit for their bed. For more guidance on your mattress fit, head to our mattress shopping guide.

FAQ:

How do I choose the best mattress for my child?

Start by choosing a mattress that matches the size of your child’s bed frame. Next, check the recommended mattress height, especially for bunk beds, loft beds, and trundles. Firmness, materials, sleeping temperature, and your child’s comfort preferences should also factor into your decision.

What mattress firmness is best for kids?

A medium-firm mattress is a popular option for children because it combines supportive comfort with gentle cushioning. Maxtrix mattresses feature layered memory foam that cradles the body, evenly distributes weight, and supports comfortable sleep.

How thick should a kid’s mattress be?

The right mattress thickness, otherwise known as mattress height, depends on the bed frame. Maxtrix offers 5", 8", and 10" mattresses. A low-profile 5" mattress provides more headroom and works well with many trundles, while 8" and 10" mattresses provide a taller, plusher sleep surface when the bed frame allows.

What mattress height should I use for a bunk bed?

A bunk bed mattress should be low enough to leave sufficient guardrail height above the sleeping surface. Always follow the mattress-height recommendation listed in the bunk bed’s product details. Maxtrix bunks feature industry-leading 16" guardrails, allowing families more flexibility when selecting a compatible mattress.

What mattress is best for a loft bed?

The best loft bed mattress fits the bed frame securely while leaving sufficient guardrail protection and comfortable headspace above the bed. Depending on the loft height and room setup, a 5", 8", or compatible 10" mattress may be appropriate.

What size mattress fits a trundle bed?

Most trundle beds work best with a 5" mattress, which allows the trundle to slide beneath the main bed. Maxtrix standard trundles fit a Maxtrix-exclusive trundle mattress, while Maxtrix XL trundles fit a standard twin-size, 5" mattress. Always check the individual bed’s specifications before purchasing.

Are memory foam mattresses good for kids?

Memory foam can provide comfortable cushioning and even weight distribution for growing sleepers. Maxtrix mattresses combine layers of memory foam with medium-firm support and are CertiPUR-US® certified for added peace of mind.