Nike Alphafly 3 vs Vaporfly 4: Which Nike Super Shoe for Your Marathon?

The verdict

We haven't run in either shoe. This comparison uses Nike's own descriptions, RunRepeat's lab measurements and the specs linked on each product card. Both shoes are sold on Amazon through third-party sellers rather than by Nike directly.

Specs side by side

The headline gap is stack: 40 mm vs 35 mm at the heel by Nike's listed figures, and 38.1 mm vs 34.1 mm in RunRepeat's lab. The weight gap is small: 7 oz vs 6.5 oz for a men's shoe by the listed figures. Both sit under World Athletics' 40 mm limit for road shoes, which applies to World Rankings Competitions.

Which suits your level

If you're racing shorter distances, our 5K and 10K race shoe picks and half marathon race shoe picks rank the racers for those distances.

The differences that matter

What Nike built each one for

Nike says the Alphafly 3 was designed "to help all athletes break barriers in the marathon no matter their pace", and calls it the Alphafly 3 marathon shoe in its Vaporfly 4 launch. It describes the Vaporfly 4 as built for "distances ranging from the 5K to the marathon," roughly 10% lighter than the Vaporfly 3. So Nike itself positions one as a marathon specialist and the other as an all-distance racer.

Cushion and construction

Both use ZoomX foam and a carbon fiber Flyplate. The Alphafly adds Air Zoom units in the forefoot, and Nike says version 3 has one continuous bottom for a smoother heel-to-toe transition and a wider full-length Flyplate for "a propulsive, stable ride." The Vaporfly is lower and simpler, with an updated Flyplate curvature per Nike.

Energy return

RunRepeat measured 74.9% heel energy return on the Alphafly 3 and 78.1% on the Vaporfly 4, which it says places the Vaporfly among the highest results it has recorded. Higher energy return on a lab rig doesn't settle the marathon question on its own; RunRepeat still points heavier marathoners to the Alphafly for its extra cushioning.

Fit and toebox

RunRepeat says the Alphafly 3 fits slightly small, with a toebox it measured at 75.3 mm and calls exceptionally broad for a racing shoe. It rates the Vaporfly 4 true to size, measured its toebox at 73.2 mm, and flags a narrow midfoot and heel. Both are listed in normal and wide.

Drop

Nike lists 8 mm for the Alphafly 3 and 6 mm for the Vaporfly 4. RunRepeat measured 8.5 mm and 8.6 mm, so in the lab the two are close.

Durability and heel strikers

RunRepeat scored the Alphafly 3's toebox durability at 1 out of 5 and notes heel strikers might wear its outsole down quickly. For the Vaporfly 4, it flags the narrow midfoot and heel as limiting stability. Neither is the ideal heel-striker shoe, which is why we list an alternative below.

RunRepeat's lab numbers side by side

Lab numbers come from RunRepeat's reviews of each shoe, linked above; they describe the pairs RunRepeat tested, not a guarantee for every size.

Your body weight and the cushion question

Specs alone don't settle this part of the decision. RunRepeat's Vaporfly 4 review is direct about it: lightweight runners will find a race-ready shoe that covers everything up to full marathons, but runners who are not on the lightweight side may find its cushioning underwhelming, and for them "a shoe closer to the 40-mm limit in the heel would probably be a smarter pick" for the marathon. The Alphafly 3, at 40 mm listed and 38.1 mm measured, is that shoe in Nike's lineup.

RunRepeat doesn't publish a body-weight cut-off, and neither do we. If you're unsure where you fall, the tie-breaker is how your legs feel at the end of your longest training runs in your current shoes: if you finish 20 miles wishing for more foam, the Alphafly is the safer marathon pick.

How each ride is built

RunRepeat's Alphafly review sums up the design split: the Alphafly's carbon plate sits closer to the foot, which it says "excels in long-distance races by boosting running economy and stability," while the Vaporfly's geometry "suits fast efforts like 5K/10Ks." Nike's own changes point the same way. For the Alphafly 3, Nike highlights a continuous bottom for a smoother heel-to-toe transition and a wider Flyplate for stability; for the Vaporfly 4, it highlights weight, calling it roughly 10% lighter than the Vaporfly 3 and 20 grams lighter than the original 2017 Vaporfly.

Put simply, Nike has spent the Alphafly's updates on marathon comfort and control and the Vaporfly's on speed and weight. Which of those matters more to you is most of the decision.

Buying and owning one

• Sizing. RunRepeat says the Alphafly 3 fits slightly small and rates the Vaporfly 4 true to size. If you plan to try both, don't assume the same size works in each.
• Where to buy. On Amazon, both are sold through third-party sellers rather than by Nike, so check the seller and the return policy before ordering.
• How long they last. RunRepeat scored the Alphafly 3's toebox durability at 1 out of 5 and says heel strikers may wear its outsole quickly. Treat either shoe as a race-day tool plus a few key sessions.
• When to buy. Early enough to test. Hal Higdon's advice for any new race shoe is at least two or three runs, including one semi-long run, before you race 26.2 in it.

Who should buy which

• First marathon, midfoot or forefoot landing: Alphafly 3.
• Heavier runner racing the marathon: Alphafly 3. RunRepeat says a shoe closer to the 40 mm heel limit would probably be the smarter marathon pick for heavier runners.
• Lighter runner who wants one racer from 10K to the marathon: Vaporfly 4.
• Racing mostly 10Ks and halves: Vaporfly 4.
• Wide or high-volume forefoot: Alphafly 3 in wide, given the broader measured toebox.
• Heel striker, first plated marathon: neither; start with the Endorphin Pro 5.

See where both sit against every other racer in our marathon race shoe ranking.

Should you own both?

Only if you race a lot of distances. For a runner with a spring 10K, a summer half and a fall marathon, the split is logical: the Vaporfly for the shorter races, where RunRepeat rates it strongest, and the Alphafly for 26.2. For most runners training for one marathon, one racer is plenty, and a second training shoe does more for an 18-week block. If you're building toward your first marathon, our first marathon shoe picks explain why the training shoe comes first and when a racer makes sense at all.

Whichever you buy, test it before race day. Hal Higdon's rule for any new race shoe is at least two or three runs, including one semi-long run in the final weeks, because blisters might not appear until after mile 20. A faster run or two and part of a long run in the new pair will tell you more than any spec table.

Alternatives worth knowing

Nike Zoom Fly 6. Not a race-day super shoe but Nike's carbon-plated trainer, with ZoomX and SR-02 foam, a carbon fiber Flyplate and a 40 mm / 32 mm stack at 8.6 oz (men's 9). It's the shoe for faster training runs, so your Alphafly or Vaporfly stays fresh for race day.

Saucony Endorphin Pro 5. RunRepeat calls it the best super shoe for beginners or runners who feel uncomfortable with unstable designs, and a very good marathon shoe for heel strikers. It's also from a brand with an official Amazon store. For more plated options across all distances, see our best carbon-plated running shoes, or use the Level Finder to check which tier you're shopping for.