Nike Pegasus 36 Trail Sizing Guide: Run Small? (33 Pairs)

Nike Pegasus 36 Trail Sizing — What 33 Pairs in the Feetlot Database Tell Us

The Nike Air Zoom Pegasus 36 Trail is a trail-running variant of the road Pegasus, and the Feetlot database holds 33 owner-reported pairs for it. The fit pattern across those owners is consistent (the typical Feetlot residual sits around 0.20 to 0.25 size units), so the shoe fits a given foot length predictably from runner to runner. Unlike many lifestyle sneakers that run roomy, the data shows this trail model runs about half a size small, which matches the common advice to size up in performance running shoes.

The reason is in the build: a snug, foot-hugging mesh upper and a performance running last that wraps the midfoot tightly for trail security. That secure fit is great for technical terrain but leaves little spare length, so most runners add half a size to keep the toes off the front on steep descents.

Should You Size Up or Down in Nike Pegasus 36 Trail?

Standard fit (most people)

Go half a size up from your true Nike size. Trail running flexes the foot forward on downhills and feet swell over long efforts, so the extra half size keeps your toes from jamming the toe bumper. Half a size up gives a secure midfoot hold with just enough room up front, according to Feetlot data.

Wide feet

Size up half, and consider trying a wide width if Nike offers it for your colorway. The Pegasus 36 Trail upper is a snug performance mesh that wraps the foot closely, so wide-footed runners feel the squeeze through the midfoot at true size. The extra half size relieves the width pressure as well as adding toe room.

Narrow feet

Staying true to size can work for narrow feet who want the most locked-in trail fit, though most runners are still better off half a size up to protect the toes on descents. The mesh upper cinches down well with the lacing, so narrow feet rarely swim even at true size. Try before a long run if you can.

Pegasus 36 Trail vs the road Pegasus 36

The Pegasus 36 Trail and the standard road Pegasus 36 share the same length sizing — take the same number in both. The Trail version adds a grippier outsole, a reinforced upper, and a slightly more protective fit, but the last length is the same. If the road Pegasus fits you at a given size, start there for the Trail.

How Nike Pegasus 36 Trail Compares to Other Sneakers

The Pegasus 36 Trail sits close in length to most lifestyle sneakers, but it runs slightly smaller than the roomiest of them. According to Feetlot data, it fits at essentially the same numerical size as Air Jordan 1, the adidas YEEZY Boost 350 V2, Nike Air Max 90, Nike Blazer Mid '77, Air Jordan 4, the Nike SB Dunk Low, and Nike Air Max 97. If a runner takes size 10 in any of those, they take size 10 in the Pegasus 36 Trail too.

The notable exceptions run roomier than this trail shoe. The Nike Air Force 1, Vans Authentic, Converse Chuck Taylor, and adidas Superstar all fit about half a size larger than the Pegasus 36 Trail — so take half a size up in the Pegasus 36 Trail compared to what you wear in those. Boot-style models run roomiest of all: the Clarks Desert Boot fits a full size larger, so add a full size to your Desert Boot number when buying the Pegasus 36 Trail.

Sign in to Feetlot and add a few of your other sneakers to get a personalized Pegasus 36 Trail size recommendation calibrated to your actual foot rather than to the population average.

Nike Pegasus 36 Trail Size Chart (US / EU / UK)

Common Sizing Mistakes

• Buying true to size like a lifestyle sneaker. The Pegasus 36 Trail runs about half a size small, unlike roomy casual shoes such as the Air Force 1. Take half a size up or your toes will hit the front on descents.
• Ignoring foot swell on long runs. Feet expand over a long trail effort. A fit that feels perfect in the store at true size often feels short after an hour on the trail.
• Treating it differently from the road Pegasus 36. Both share the same length last. If you size up half in the road version, do the same in the Trail.
• Sizing up a full size. A full size up leaves slack that lets the foot slide forward on steep terrain, which causes more toe trauma than a snug fit. Half a size up is the sweet spot.
• Buying small expecting the mesh to stretch. The performance mesh upper conforms to width but does not gain meaningful length. Too short stays too short.

How Feetlot Computes These Numbers

Every Nike Pegasus 36 Trail sizing recommendation on Feetlot is the output of a global offset model fit to over 100,000 owner-reported shoe records. Each shoe gets a single number — its "size offset" — that captures how much its sizing drifts from the reference shoe (the Nike Air Force 1). When a Feetlot user provides their size in any tracked sneaker, the model recovers their true foot baseline and recommends the matching Pegasus 36 Trail size.

This works better than the more common pairwise approach because Feetlot uses the entire wardrobe graph. A YEEZY 350 owner contributes data about how YEEZY fits relative to AF1 owners, which links to runners who own both road and trail Pegasus models, and so on. Even when two users share zero shoes directly, the chain of users in between transmits a consistent recommendation. The result: sizing advice that holds up no matter how unusual a wardrobe is.