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Shopping for a new baby can be a very stressful ordeal. From baby bottles to nappies to a million other odds and ends, it can sometimes be difficult to figure out which ones are absolute necessities and which ones are not. But the first thing you should really be getting is a crib and of course, the mattress that comes with it. And getting the right dimensions for the crib mattress you need is where you start.
Crib mattress dimensions in inches
| Crib Mattress Size | Dimensions |
|---|---|
| Standard crib mattress | 28" x 52" |
| Mini crib mattress | 24" x 38" |
| Shaped crib mattress | 28" x 52" (varies) |
| Toddler bed | 28" x 52" (varies) |
A standard crib mattress size measures 28 inches in width and 52 inches in length.
While most new parents usually get a standard size crib mattress, there are other crib mattress sizes (and types) available such as mini crib mattresses and shaped crib mattresses.
A mini crib mattress measures 24 inches in width and 38 inches in length.
Shaped crib mattresses circumference can vary by a few inches more or less than a standard size crib mattress.
Toddler beds, on the other hand, can either be the same size (in the case of convertible cribs) or slightly larger that a standard crib mattress but they’re not quite a (big) kids’ mattress such as a twin size bed. A standard sized toddler bed measures 50-60 inches in length whereas a twin bed is 80 inches long.
Standard crib mattress size
A standard crib mattress size measures 28 inches in width and 52 inches in length.
A standard crib mattress is the most commonly bought crib mattress size in the US. A standard sized crib mattress can fit even a larger than average baby with a lot of room to spare (not that newborns move around a lot anyway).
What’s more is that a standard crib mattress can last you a good few years – or at least until your baby starts to climb out of his/her crib.
Some standard cribs have bases and sides that can be lowered or elevated, making it easier for you to take your baby out of the crib.
Standard crib mattresses can come in different firmness levels although most – if not all – crib mattresses are made only out of foam. These types of foam can either be poly foam, memory foam or latex foam. Choose latex foam crib mattresses if you would prefer an organic mattress for your baby.
Most standard sized baby’s mattresses come with waterproof covers. They can also vary wildly in price depending on type, material and brand.
Mini crib mattress size
A mini crib mattress measures 24 inches in width and 38 inches in length.
Smaller than standard crib mattress by a good 14 inches in length and 4 inches in width, mini crib mattresses are mostly chosen by new parents who do not have enough room in their house for a proper nursery or as a temporary bed for their smaller than average newborn.
Mini cribs are also great for parents of twins (or more) who need two separate cribs that can fit into a nursery or a shared room.
Mini cribs should not be confused with a bassinet even though they are almost the same size. A mini crib mattress may be smaller than standard crib mattresses but it’s still a good sized crib that can fit a newborn baby of any size.
Just like a standard crib mattress, a mini crib mattress comes in different types of foam mattresses from memory foam to latex. They come in different firmness levels as well and usually come with a built-in waterproof mattress cover.
Because of their smaller size, they are also cheaper than standard crib mattresses although this may also depend on the type and brand of mattress.
Shaped crib mattresses
A shaped crib mattress can be the same size as a standard crib mattress (28 inches in width and 52 inches in length) or can be a few inches bigger or smaller.
Shaped crib mattresses are – as the name suggests – crib mattresses come in shape in ovals or circles (some customized one can even come in semi-circles).
The shaped crib mattress size is pretty common but not all mattress brands carry it – you have to go to specialty stores to get them and they usually come as a package deal for both the mattress and the crib.
Hence why shaped cribs tend to be more expensive than basic crib sizes.
It really is a matter of taste and preference when new parents choose shaped cribs. Most sizes of crib mattresses and baby cribs can fit into any room or nursery quite easily. A shaped crib mattress and crib serves a more aesthetic purpose than anything.
As with all crib mattresses, a shaped mattress comes as a foam mattress which can range from poly foam, specialty proprietary foam or latex foam. They also come with a waterproof cover.
How to measure your crib
Measuring a crib to get the correct crib mattress size is pretty straightforward but you need to measure the interior dimensions since cribs hold in a mattress differently than standard bed sizes.
All you need is measuring tape.
First, measure the exterior of the crib itself, railings and all. Next measure the interior of the crib which would then tell you the exact crib mattress size you would need. If you plan to use a mattress protector with your crib mattress, take that into consideration as well.
How to choose a baby crib mattress
The right crib mattress size really depends on a lot of different factors but the most important thing you should consider as a parent (new or otherwise) is to create a safe sleeping environment for your baby.
Breathability
You may already know this but infants tend to have a higher body temperature than older children and adults. This means they can get hot pretty easily and hot sleepers are cranky sleepers (be it adult or infant).
Choose a crib mattress that features breathable foam such as latex or specialty foam that promotes constant airflow. Also choose a crib mattress that features a mattress cover with good temperature regulation.
Important note: studies have also shown that overheating can contribute to sudden infant death syndrome or SIDS so be very particular when it comes to choosing a breathable mattress.
Firmness
Most crib mattress are medium to firm when it comes to firmness levels. Newborns sleep on their backs but once they learn how to roll over, they can sleep on their stomachs, sides or a combination of all three sleeping positions. A medium to firm crib mattress is best to accommodate all sleeping positions. A softer mattress, on the other hand, may hinder movement.
If you’re concerned that the crib mattress you chose might be too firm, you can soften up your infant’s bed by adding a crib quilt. But be wary, adding a lot of crib quilts and/or pillows can contribute to smothering so always opt for less, especially when your child is a newborn.
Durability
Let’s face it.
What with formula spills and frequent ‘accidents’, a crib mattress is going to go through so much in its lifetime. Choose a crib mattress that features a removable, waterproof cover that can be washed and dried.
This contributes to its longevity since foam breaks down pretty quickly when exposed to liquids frequently. Some crib mattresses even come as a reversible crib mattress.
Price
Just like standard mattresses, a crib mattress’ price range can vary from pretty cheap to hella expensive. It all depends on brand, materials and size.
Typically, shaped crib mattresses tend to be on the more expensive side of the spectrum while standard crib mattresses stay within a happy medium. Mini crib mattresses are the cheapest.
Find something that fits both your needs and budget range.
Non-toxic materials
Although crib mattresses usually only come as foam mattresses, which are man-made, you can still choose ones that are made with no toxic chemicals whatsoever. Look for certifications such as CertiPUR-US and Greenguard Gold.
Natural latex foam crib mattresses are also widely available if you prefer organic mattresses.
FAQs
In the US, the United States Consumer Product Safety Commission explicitly states that crib mattresses should not exceed 6 inches so all crib mattresses in the USA are 6 inches or less.
A toddler bed can either be the same size as a standard crib mattress but they can also be slightly bigger, depending on mattress brand. A standard toddler bed measures 28″ x 52″ which is the same as that of a standard sized crib.
Conclusion
Not all crib mattresses are the same size and in the case of shaped cribs – come in ovals or circles. Depending on your needs and budget, you can choose from either a standard crib mattress, a mini crib mattress or a shaped mattress.
Some standard crib mattresses are convertible which means it can be transitioned into a toddler bed when your infant turns into toddler age.
Michelline loves nothing more than a cozy bed, with a stack of books at her side. She loves getting lost when she travels, can bake an entire British afternoon tea from scratch, is obsessed with all things analogue and does calligraphy on the side. She currently suffers from mild insomnia and is more than happy to be your guinea pig, so you won’t have to go through all the trouble of finding out what works best for you.
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