Our hands-on Scarpa Booster S Review yielded some surprising results!

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The Scarpa Booster S climbing shoes were designed to be a softer version of the Boostic. They have an extremely lightweight build (only 200 g as opposed to 240 g for the Boostic) and are suitable for steep walls.

Their excellent precision and edging makes them great projecting shoes for bouldering or overhung sport routes.

If you’re interested in a shoe that looks good and works hard, the Velcro straps, bright colors and sleek design are an added aesthetic bonus to this attractive shoe!

The weaknesses of the Booster S are solely on terrain that it is not intended for (i.e. slabs and long, vertical walls), and we wouldn’t recommend this shoe for brand new climbers.

Read on for our full Scarpa Booster S review, or compare them to other options in our list of the best climbing shoes.

Product Specs

  • Weight: 200 g (7oz)
  • Upper: Microsuede
  • Sole: Vibram XS Grip2; 3.5 mm
  • Sizes: 35-45
  • Color: Yellow, Orange, Blue, and Black

The lightweight build and new rubber are the two biggest differences between the Scarpa Boostic and the Booster S.

The Vibram XS Grip2 is a sticky rubber that is noticeably softer than the Boostic’s Vibram XS Edge rubber and is often found on high-performance bouldering shoes. The rubber has durability consistent with other bouldering shoes and shows minimal wear on the rand around the toe box after a few months of use.


EDGING 5 out of 5 stars (5 / 5)
These shoes are designed for tough edging problems; we’re talking steep walls with tiny feet.

The talon-like toe box of the Scarpa Booster S makes sticking and edging on the tiniest of feet feel solid. The Booster S is built with Tri-Tension Active Randing which essentially pulls the support and rand of the shoe towards the tip of your big toe, improving precision and power on edging.

POCKETS 3.5 out of 5 stars (3.5 / 5)
The toe box of the Booster S is a bit larger than other climbing shoes like the Boostic due to the aggressive turn down of the toe and the rubber plating on the top of the toe box.

This means that the smaller the pocket or crack, the more difficult it will be to push your toe into (but it will certainly stick once it’s in there!); this can be improved through breaking the shoe in to your specific needs.

HEEL HOOKING 5 out of 5 stars (5 / 5)
Scarpa Booster S Heel The heel cup on this shoe is very solid and comfortable. I found it to be smaller than many other shoes which worked great for my heel.

Additionally, the heel cup is one of the most interesting looking heel cups I have climbed in (think rubber armadillo plates). The design of the heel cup and lack of rubber on the arch of the foot make the heel cup look more pronounced, and seems to help it stick into tricky heel positions.

This shoe has had one of the more solid heel cups of those I have tried.

TOE HOOKING 4.5 out of 5 stars (4.5 / 5)
Scarpa Booster S toe box The plated heel cup design is also found on the rubber patch on top of the toe box.

This design improved my grip and confidence on toe hooks when using these shoes. The arch in the toe box makes them a little more painful to break in for toe hooking, but once you do they are worth it.

SENSITIVITY & PRECISION 5 out of 5 stars (5 / 5)
These are extremely sensitive bouldering shoes due to an ultra-thin support ribbon that starts on the inside of the shoes and then wraps up and around the toe box.

The ribbon improves the support of the shoe without compromising sensitivity and keeping the shoes extra light. It also puts less material between the tip of your toes and the climbing rubber.

These shoes were built for sticky precision and they prove it on your projects. The downturned toe box and aggressive point make the smallest, slickest foot holds feel more secure.

SMEARING 3 out of 5 stars (3 / 5)
This is certainly not a shoe designed for smearing on vertical/slab walls and weighting the entire foot.

The aggressive, downturned toe and minimal rubber in the arch of the foot mean that the Booster S is not the shoe to use on slab. Any attempts that I have made to use these shoes on slab have ended painfully.

That being said, if there is smearing on an overhang, the super sticky Vibram XS Grip 2 rubber will keep your foot on the wall.

Sizing, Fit, & Comfort

It took me two tries to find a suitable size for the Booster S.

I was expecting to have to size down from my street size (Women’s size 9), but that ended up being too tight to break in. I ended up with the same size as my street shoe and this was tight enough that when I broke them in, they were still snug and good for projecting.

If you aren’t used to Scarpa shoes, and typically size down, plan on getting these shoes someplace that you can try on multiple sizes before making a decision. I thought the Booster S fit pretty well throughout the foot and heel cup for my average sized feet. I would recommend either going up half a size or planning on a longer break-in period if you have wider feet.

The shoes didn’t stretch too much once broken in, and the aggressive down turn of the toe box hasn’t really flattened out. I don’t use these shoes on vertical routes where I would be putting a lot of pressure on the ball of my foot, and I take them off between climbs. This may help preserve the arch through the shoe. Either way, they have stayed suitable for projecting while improving in comfort.

Scarpa Booster S size

One of my favorite features of these shoes is the tongue beneath the Velcro straps. It’s made out of durable microsuede that is soft and keeps the straps from pinching the tops of my feet. This has made these particular Velcro shoes more comfortable than other Velcro climbing shoes I’ve used before.

As for comfort, these shoes definitely aren’t for lounging between problems. The aggressive arch mixed with a pretty thick rand makes them generally uncomfortable on flat ground. Fortunately, the Velcro comes off and on easy, so it’s alright to take them off between attempts.

The break-in period took longer than other shoes have in the past. One difficulty is that these shoes aren’t as comfortable on more vertical/slabby terrain. This meant that I could break them in during my warm-ups and instead relied on projecting sessions to do the work for me.

Eventually they became comfortable; it just took longer than I’ve found for less aggressive shoes.


The greatest attributes of Booster S — namely its aggressive turn, precise toe box, and form-fitting heel cup — have all survived a few months of gym climbing.

The ultralight build of these shoes may lead to them wearing out sooner, so I’d recommend taking them off between projecting attempts and keeping them clean to make them last as long as possible.


As an added bonus, these shoes look cool.

I’m not sure whether it’s the vibrant colors or the sleek look, but I’ve been climbing in climbing gyms for many years, and I’ve never had more people comment on my shoes as when I’m wearing my Booster S’s.

During one gym climbing session, after finishing up on a project, a spotter described my feet as residing in “the Cadillacs of climbing shoes.” I’ll take the compliment!

Final Thoughts

I would strongly recommend this shoe to people who need a lightweight, aggressive, well-fitting shoe for steep, single-pitch sport routes and bouldering, either in the gym or outside.

If you’re looking for a shoe that can aid with precision on difficult feet and gives you confidence in your heel hooks (and makes you look good doing it), this may be the shoe for you!

You wouldn’t want to buy this shoe as a novice climber or for long vertical/slab climbing. Spend some time getting the perfect fit, planning on it being close to your street shoe size, and go send those projects!

This review was conducted by an infrequent contributor to the site.


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