Ask ten people what the perfect level of firmness is for a mattress and you're almost guaranteed to get ten different answers.
Firmness is one of the biggest factors in how a mattress feels, yet there's no universal standard. What one business describes as "medium" another might label "firm."
This guide breaks down what mattress firmness actually means, how the common firmness scale works, and how to narrow down the right level based on how you sleep, your body type, and who the mattress is for.
What Is Mattress Firmness (and How It Differs from Support)
It's important to first clarify that firmness and support are two different things, though they're often used interchangeably.
Firmness describes how a mattress feels when you first lie down: the initial physical sensation of softness or resistance against your body.
Support refers to how well the mattress keeps your spine aligned while you sleep.
A soft mattress can still be supportive if the core material holds your body in proper alignment. A firm mattress can lack support if it doesn't contour enough to fill the gap under your lower back or between your shoulders. The two work together, but they aren't interchangeable.
When people say a mattress is "uncomfortable," they're usually reacting to firmness. When they wake up with aches, the issue is more likely to be support. Getting both right is crucial to a good night's sleep.
The Mattress Firmness Scale Explained
Most mattress brands and reviewers use a 1 to 10 scale, where 1 is extremely soft and 10 is like sleeping on a hard floor. The middle of the scale, around 5 to 7, is where most adult mattresses sit. Here's how the firmness bands roughly break down:
• Soft (1–3): Deep sinking, significant contouring. A plush mattress meaning one that lets your body press well into the surface, with very little resistance.
• Medium (4–6): A balance of cushioning and pushback. You sink in at the shoulders and hips but still feel held. A medium to firm mattress sits at the upper end of this band, around 5 to 6.
• Firm (7–10): Minimal sinking. A firm mattress meaning the surface stays relatively flat under your weight, with strong resistance. The 9–10 range is rare in consumer mattresses and usually reserved for specific therapeutic needs.
There's no industry regulator enforcing these numbers. A "6" from one manufacturer won't feel the same as a "6" from another. The scale is useful for comparing mattresses within a single brand's range, but less reliable across different brands or materials.
How Latex Compares to Foam and Spring on the Firmness Scale
The material inside a mattress affects how firmness actually feels in practice.
Memory foam moulds closely around your body and responds slowly. Initially it can feel softer than its rating suggests because of how deeply it lets you sink before resistance kicks in. It also tends to soften with heat and wear over time, which means the firmness you buy isn't always the firmness you keep.
Innerspring mattresses feel firm on the surface but their support depends on the coil gauge and arrangement. They can lose tension as springs fatigue, leading to sagging in high-pressure areas.
Organic latex mattresses behave differently again. They have a natural bounce and responsiveness, so rather than slowly sinking in, your body is gently pushed back. A medium-firm latex mattress tends to feel more buoyant than a memory foam mattress at the same firmness level. It's also worth noting that latex mattresses also hold up well in terms of density over time.
Latex doesn't soften with body heat, and its open cell structure means it won't develop the permanent impressions that synthetic foams are prone to. For people buying a mattress online and worrying about long-term firmness consistency, this is a meaningful difference.
How to Choose the Right Firmness for You
Sleeping Position
Side sleepers generally do best on a soft to medium mattress. The shoulders and hips need to sink in enough to keep the spine level. Back sleepers tend to prefer medium to medium-firm, which supports the natural curve of the lower back without creating pressure points. Stomach sleepers usually need firmer support to prevent the hips from dropping and straining the lower back.
Body Weight
Lighter people (under about 60 kg) don't compress a mattress as much, so a medium mattress will feel firmer to them than it would to someone above a 60kg weight. Sleepers with more body weight (over about 100 kg) tend to sink further into any surface, and a firmer mattress provides better support and durability in those cases.
Shared Beds and Partners
When two people share a bed and prefer different firmness levels, a medium-firm mattress is often the practical compromise. Latex mattresses handle this scenario well because their bounce means less motion transfer than innerspring, and they don't create the 'roll together' dip.
Existing Back or Joint Pain
People with lower back pain are often recommended a medium-firm mattress, as this level tends to balance spinal alignment with enough cushioning to relieve pressure points. Those with shoulder or hip pain may benefit from something slightly softer to reduce pressure in those areas. If pain is chronic, it's worth discussing mattress choice with a physiotherapist or osteopath, as ongoing pain isn't always caused by the mattress itself.
Firmness for Kids' and Babies' Mattresses
Babies and young children need firmer mattresses than adults. For infants under 18 months, Australian safe sleeping guidelines recommend a firm, flat surface, and our cot and bassinet mattresses are built to that standard. There should be no noticeable impression when you press your hand into the mattress. A surface that's too soft increases the risk of suffocation.
For toddlers and older children, a medium-firm to firm mattress supports growing bodies and developing spines. Softer mattresses don't provide enough resistance for lighter body weights, which can lead to poor alignment. As children move into their teenage years, a medium-firm mattress remains a solid starting point, adjustable as their body weight and sleeping habits change. Our popular children's mattresses collection is built around this age group specifically.
Our Mattress Range by Feel
Every mattress in the The Natural Bedding Company's range is handcrafted in our Sydney workshop using certified organic latex, and firmness varies across the collection based on latex density, layering, and whether a coir (coconut fibre) core is included for added structure.
On the softer, more cushioned end of the range sits Aether, Cloud 9, Cloud 7, and Deluxe floating between plush to the medium and medium-firm range, balancing comfort with support.
The Luna, Aurora, Artemis, Supreme, and Sovereign Rest sit at the firmer end, with coir-core options providing the most structured feel.
Feel is subjective, and this ordering is based on comparison within our range alongside customer feedback. Visiting our Sydney showroom is the best way to feel the difference for yourself.
Can't Decide? Start Firmer and Add a Topper
If you're buying online and torn between two firmness levels, go with the firmer option. You can always soften a firm mattress by adding a latex topper or a wool and latex topper on top. Going the other direction, making a soft mattress firmer, is much harder to do.
A topper also lets you fine-tune the feel over time, or adjust for a partner who prefers a different sleeping surface on their side of the bed.
Frequently Asked Questions
What is the best level of firmness for a mattress?
There's no single best firmness. It depends on your sleeping position, body weight, and personal preference. Most adults are comfortable in the medium to medium-firm range (around 5–7 on a 10-point scale), but side sleepers and lighter individuals may prefer something softer, while stomach sleepers and heavier people tend to do better with firmer support.
What firmness level are most hotel mattresses?
Most hotel mattresses fall in the medium to medium-firm range, typically around a 5 or 6. Hotels aim for a feel that suits the widest variety of sleepers, which is why they tend to avoid anything too soft or too firm.
Is it better to sleep on a firmer or softer mattress?
Neither is inherently better. A firmer mattress may help people who sleep on their back or stomach, while a softer mattress may relieve pressure for side sleepers. The right choice is the one that keeps your spine aligned without creating discomfort at your pressure points.
How do I tell if my mattress is too firm or too soft?
If you wake up with numbness, tingling, or pain in your shoulders and hips, your mattress may be too firm. If you wake with lower back pain or feel like you're sinking into a hammock, it's likely too soft. Your spine should maintain its natural curve when you're lying down.
What is the best mattress firmness level for back pain?
A medium-firm mattress is often recommended for people with back pain, as it tends to provide enough support for spinal alignment while still cushioning pressure points. That said, the right firmness depends on where the pain occurs and your sleeping position. Persistent or severe back pain warrants advice from a healthcare professional.
