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Footwear

Footbed

Also called insole, sock liner

What is a footbed?

A footbed is the cushioned, usually removable layer your foot rests on inside a shoe or boot, and what most people call the insole. Stock footbeds are typically inexpensive fillers, and replacing one with a supportive aftermarket insole is the cheapest way to change how a boot fits.

Footbed at a glance

Also called
Insole, sock liner
Aftermarket lifespan
About 12 months
REI, for regular use; longer for occasional use
Hiking boots suit
High-volume insoles

Is a footbed the same as an insole?

In a shop, yes. REI uses insole and footbed as two names for the same removable layer, and that is how most hikers use the words. The piece you pull out of a boot, stand on to check your size and replace with an aftermarket one is the footbed.

Shoemakers draw a finer line. In shoe construction the insole is the board the upper is built onto, and the footbed, also called the sock liner, sits on top of it. You will only meet that distinction if you read about how a boot is made.

Why replace the footbed a boot comes with?

Because it was rarely the point. REI describes stock insoles in performance boots and shoes as typically inexpensive fillers, and says aftermarket insoles can better tailor fit, support and comfort to your feet. The support insoles it sells get their comfort from a firmer structure that stabilizes the foot, not from extra cushioning.

A swap can also fix fit. REI notes that a shoe that fits well in the forefoot but lets the heel slip may improve with a supportive mid to high volume insole, which takes up excess space at the back and steadies the heel.

What does insole volume mean?

Volume is how much room the insole takes up inside the shoe, and it usually tracks arch height. REI's guidance is that high-volume insoles suit high-volume footwear such as hiking boots and typically work best with high arches, medium-volume insoles fit average shoes and a range of arches, and low-volume insoles suit snug footwear and very low arches.

Take the stock footbed out before trying a new one, which REI also reminds you to do. Stacking two changes the fit of the whole boot, and the point of the test is to judge the new insole in the space it will actually occupy.

What this means when you're choosing

  • A removable footbed, which leaves room for an aftermarket insole or an orthotic
  • Insole volume that matches the footwear and your arch, which for most hiking boots means high volume
  • A firm, supportive insole rather than a soft cushion if your heel slips
  • Wear on the insoles you already have, since REI puts aftermarket insoles at about 12 months of regular use

Footbed vs Midsole

FootbedMidsole
Where it sitsInside the shoe, directly under your footBuilt into the sole, below the footbed and above the outsole
RemovableUsuallyNo
Main jobFit, support and comfort where your foot touchesCushioning and structure for the whole shoe
When it wears outReplace it on its ownThe shoe is usually done

Which to pick: A tired or generic footbed is a cheap fix and a dead midsole is not, so work out which one is the problem before buying insoles to rescue a worn-out shoe.

The common mistake

Buying the softest insole on the shelf

Soft and cushy feels good in the shop and does little for a foot that is sliding or rolling. REI's point about support insoles is that the comfort comes from stability, not padding. If the problem is fatigue, heel slip or arch pain, look for a firmer, structured insole in the right volume.

Common questions

How often should you replace insoles?

REI puts aftermarket insoles at about 12 months for daily or regular use, and several years for a pair in footwear you only wear occasionally or seasonally. Check them now and then and replace them when they show wear.

Can a new footbed fix a boot that doesn't fit?

It can fix small problems, such as a little too much volume or a slipping heel. It cannot fix the wrong length or the wrong shape of last, and a boot that hurts in one specific spot usually needs replacing rather than padding.

Where this is defined

Where this comes up

Guides on Tom's Hiking where footbed changes which product is right for you.

More in footwear

Lug depth

Lugs are the raised blocks on the sole of a boot or trail shoe, and lug depth is how tall they are, usually 3 to 6 mm. Deeper lugs bite into soft ground; shallower ones give more contact area on rock and hard trail.

Outsole

The outsole is the rubber layer on the bottom of a shoe, the part touching the ground. It carries the lug pattern and the rubber compound, which together decide grip, and it's usually the first part of a shoe to wear out visibly.

Midsole

The midsole is the foam layer between the outsole and your foot. It absorbs impact and sets how stiff or soft a shoe feels, and it's the part that quietly dies long before the tread looks worn.

EVA foam

EVA is the light, springy foam most hiking and running midsoles are made of. It cushions well and weighs little, but it compresses permanently over time, which is why shoes go flat after a few hundred miles.

Stack height

Stack height is how much material sits between your foot and the ground, measured in millimetres at the heel and forefoot. More stack means more cushioning and less ground feel; less means more feedback and a lower, more stable platform.

Heel-to-toe drop

Drop is the height difference between a shoe's heel stack and its forefoot stack, given in millimetres. Zero drop means the foot sits level; 8 to 12 mm tilts you forward slightly and shortens the load on the calf and Achilles.

Rock plate

A rock plate is a thin stiff sheet, usually TPU or a nylon composite, embedded in the forefoot of a shoe. It spreads the load from a sharp rock across the whole foot instead of letting it press into one point.

Shank

A shank is a stiffening insert running through the arch of a boot, made of steel, nylon or composite. It controls how much the boot twists and bends, which is what lets a boot support a heavy load and edge on rock.

Rand

A rand is a strip of rubber bonded around the lower edge of a boot's upper, most often at the toe. It takes the abrasion from rock and roots that would otherwise wear through fabric or leather, and it protects your toes from impact.

Gusseted tongue

A gusseted tongue is sewn to the sides of the boot with fabric panels instead of hanging free. It seals the gap along the laces so grit and water can't get in, and it stops the tongue sliding sideways as you walk.

Vibram Megagrip

Megagrip is a Vibram rubber compound formulated for grip on wet and dry rock. It's softer and stickier than standard hiking rubber, which is why it holds on slabs and greasy roots, and why it wears out faster.

Gaiters

Gaiters are fabric sleeves worn over the top of a shoe or boot to keep grit, snow and water out. Low trail gaiters cover the collar and stop scree filling your shoes; tall gaiters run to the knee and seal the leg against deep snow and wet brush.

Microspikes

Microspikes are elastomer harnesses with short chains and spikes, roughly 10 to 15 mm, that stretch over a shoe for traction on packed snow and ice. They are the middle rung between yaktrax-style coils and full crampons, and they are not mountaineering equipment.

Crampon

A crampon is a metal frame carrying 10 or more points up to 5 cm long that binds rigidly to a stiff-soled boot, so a climber can stand on hard alpine ice and steep snow. It is the tier above microspikes, and it is technical equipment that needs an ice axe and training.

Insulation weight in grams

Insulation weight is the mass in grams of one square meter of the insulating sheet inside a boot or glove. A 400g boot uses a heavier sheet than a 200g boot, so it is warmer, but it is nothing like twice as warm.

Vibram Arctic Grip

Arctic Grip is a Vibram outsole technology built for traction on wet ice. It stays pliable at temperatures where ordinary hiking rubber goes hard, which is the reason a winter sole grips where a three season one skates.

Flotation

Flotation is how well a snowshoe keeps you on top of snow instead of sinking into it. It is a function of deck surface area measured against your loaded weight, which is your body plus clothing, boots and everything in your pack.

Heel lift

A heel lift is a small wire or plastic bar behind the heel of a snowshoe that flips up so your boot rests on it during a climb. It stops your calf being held at full stretch on sustained steep ground.

Heel counter

A heel counter is the stiffened section at the back of a shoe or boot that wraps around and holds your heel. It keeps the heel from sliding and rolling inside the shoe, which is where both stability on uneven ground and a blister-free heel start.

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