Nike Air Zoom Structure 21

Name: Nike Air Zoom Structure 21
Brand: Nike
Rating: 4.2 (14 reviews)

Daily trainer · Stability · Road · 9.5 oz · 10mm drop

Discontinued — we no longer see this shoe in stock. The Nike Air Zoom Structure 22 replaced it

How it ranks

The Nike Air Zoom Structure 21 trails most daily trainers in our data. Looks and durability are its strongest sub-ratings. Comfort scores well below its other sub-ratings. The rating is based on 14 runner reviews and 6 other rated shoes in the Air Zoom Structure product line.

Below average

Overall

Below average 65

Appearance

Good 81

Durability

Decent 74

Value

Below average 66

Cushioning

Below average 63

Comfort

Bottom-tier 55

Confidence

How settled the rating is against every other rated shoe. A shoe can rate high on confidence with relatively few reviews of its own when its product line has a long record and external ratings from retailer sites agree. Confidence is low when we have few ratings or when runners disagree.

See the product line's history

Confidence

93 High

High 93

Based on

The bars show roughly how much each source contributes to this shoe’s rating. Their influence depends on how many reviews we’ve collected, how many earlier versions are in the product line, and the external ratings available.

Product line track record
Our ratings
External ratings

What runners say

“The Structures have lasted beyond that average, but at $120 for a standard shoe, I would never pay full price for them.”

4/5 Full review 60 mpw training for a half marathon came from the Brooks Ravenna 8

“After about 8 months of use, I no longer have PF. Gone.”

3/5 Full review 1 mpw came from the Saucony Triumph ISO 5

“I had to swap the inner soles as the originals caused blisters on longer runs.”

3/5 Full review 10 mpw training for a half marathon came from the Mizuno Wave Inspire 12

“The structures have a nice design and effective support for my overpronation.”

4/5 Full review 50 mpw training for middle distance came from the Nike Air Zoom Pegasus 34

“This shoe is very durable except for mine get worn down very quickly because I have a heel strike and run many miles.”

5/5 Full review 35 mpw training for middle distance came from the Nike Air Zoom Structure 20

“The only complaint about EVA material is it freezes in sub 32 temps.”

4/5 Full review 50 mpw training for a marathon

“It is comfortable and I do not have issues with my heel or any pain in the feet.”

3/5 Full review 1 mpw came from the Saucony Triumph ISO 5

“The cushioning is a little firmer than I would like when running on hard concrete.”

4/5 Full review 50 mpw training for middle distance came from the Nike Air Zoom Pegasus 34

“Heavy trainer that will put in the miles if you don't care about fashionability.”

4/5 Full review 82 mpw training for a half marathon came from the Nike Air Zoom Pegasus 34

“It is not very flexible, due to the dynamic stability feature in the midsole, but for those that wear support shoes, this is no surprise.”

4/5 Full review 70 mpw training for middle distance came from the Nike Air Zoom Structure 20

“After 50-100 miles these shoes really become comfortable.”

4/5 Full review 65 mpw training for a half marathon came from the Nike Air Zoom Pegasus 34

“The shoe has been responsive, light, and pretty durable.”

5/5 Full review 30 mpw training for a half marathon came from the ASICS GT-1000 5

“There is just enough cushioning, although not an overwhelming amount.”

4/5 Full review 70 mpw training for middle distance came from the Nike Air Zoom Structure 20

“Helps with my extreme pronation.”

5/5 Full review 50 mpw training for a half marathon came from the Nike Air Zoom Pegasus 34

“I love the responsiveness and seamless upper.”

5/5 Full review 15 mpw came from the Brooks Ravenna 8

“There is more cushioning in the forefoot than the Structure 20.”

4/5 Full review 70 mpw training for middle distance came from the Nike Air Zoom Structure 20

“I just hate the price tag.”

5/5 Full review 30 mpw training for a half marathon came from the ASICS GT-1000 5

“Nice soft ride and good support.”

3/5 Full review 10 mpw training for a half marathon came from the Mizuno Wave Inspire 12

“Very durable and well built.”

5/5 Full review 50 mpw training for a half marathon came from the Nike Air Zoom Pegasus 34

Prefer this shoe over another

41% 7/17

Where to buy

No offers available

Affiliate links included. They never affect our ratings.

Prices updated daily. Last checked Oct 22.

Pros

Durability averages 4.4 out of 5 across fourteen reviews, and three reviewers call it durable, one of them wearing Structures since 1998.
Three reviewers who overpronate say the stability works for them.
Appearance averages 4.4 out of 5, and three reviewers like the looks and the seamless upper.

Cons

Three reviewers say $120 is too much, and value averages 4.1 out of 5, the lowest of its dimensions.
One reviewer swapped the insoles to stop blisters on longer runs, and another needed 50 to 100 miles of break-in.
One reviewer finds the cushioning firmer than they would like on hard concrete.

Air Zoom Structure 21 rates 65. This shoe has high confidence. See how we rate shoes.

Better Shoes Rating of prior versions of the Nike Air Zoom Structure

Each dot is one version of the Air Zoom Structure, placed by its rating and release year. The gold dot is this shoe.

Rating

40 60 80 100

64 2016 73 2016 63 2016 65 2017 72 2018 72 2023 77 2021

Release year

We use the reviews of past versions to inform this shoe’s rating. See why.

Air Zoom Structure 24

2021 · 4 reviews

77 Decent

83 Confidence
Air Zoom Structure 23

2023 · 6 reviews

72 Decent

79 Confidence
Air Zoom Structure 22

2018 · 21 reviews

72 Decent

95 Confidence
Air Zoom Structure 21 This shoe

2017 · 14 reviews

65 Below average

93 Confidence
Air Zoom Structure 20

2016 · 9 reviews

63 Below average

84 Confidence
Air Zoom Structure 19

2016 · 8 reviews

73 Decent

88 Confidence
Air Zoom Structure 18

2016 · 28 reviews

64 Below average

98 Confidence

Runner Ratings

14 ratings

5/5 5

4/5 7

3/5 2

2/5 0

1/5 0

See written reviews Write a review

Specs & fit

Sizing and ride details at a glance.

Weight: 9.5 oz
Men's / women's: Men's 10.4 oz · Women's 8.5 oz
Release: 2017 Q3
MSRP: $120
Drop: 10mm

Runner reviews

Write a review

Structure 21 Experience

4/5

Overall

This is my most commonly purchased shoe, it tends to fit my foot very well. There is just enough cushioning, although not an overwhelming amount. I felt as if there is more cushioning in the forefoot than the Structure 20. It is not very flexible, due to the dynamic stability feature in the midsole, but for those that wear support shoes, this is no surprise. They did a great job with the design of this shoe, with the color fade on the lateral side of the midsole, in my opinion. Overall, I am very happy with this iteration, Nike continues to make a great support shoe.

Anonymous runner · Nov 21, 2018

70 mpw training for middle distance came from the Nike Air Zoom Structure 20

Comfort: 4/5
Cushioning: 4/5
Durability: 4/5
Appearance: 5/5
Value: 4/5

Needs a break in period

4/5

Overall

I found that after 50-100 miles these shoes really become comfortable and my go to trainer for easy runs.

RoseCityTC · Oct 16, 2018

65 mpw training for a half marathon came from the Nike Air Zoom Pegasus 34

Comfort: 4/5
Cushioning: 4/5
Durability: 5/5
Appearance: 4/5
Value: 5/5

Great shoe, but I'd never pay full price for it

4/5

Overall

This shoe was my first foray into serious training in Nikes. Previous shoes were mostly Brooks Ravennas and Saucony Guides. I'm a bigger guy (6'3" 180 lbs) but still train pretty seriously (low 15's 5k, mid 25's 8k, 70ish half). What I find with being bigger is that I blow out the cushioning before the tread really begins to wear down. This can happen within 6-8 weeks, so I go through shoes pretty quick. The Structures have lasted beyond that average, but with how ridiculous shoe prices have gotten (around $120 for a standard shoe) I would never pay full price for them. It's just too much money to throw away. All in all, the Structures are a great shoe, but they're not $120 great.

Ball Zach · Oct 3, 2018

60 mpw training for a half marathon came from the Brooks Ravenna 8

Comfort: 4/5
Cushioning: 4/5
Durability: 4/5
Appearance: 5/5
Value: 3/5

Good stability shoe

3/5

Overall

Nice soft ride and good support. I had to swap the inner soles as the originals caused blisters on longer runs

jandre78 · Oct 3, 2018

10 mpw training for a half marathon came from the Mizuno Wave Inspire 12

Comfort: 3/5
Cushioning: 3/5
Durability: 3/5
Appearance: 3/5
Value: 3/5

Solid trainer

5/5

Overall

I've enjoyed returning to Nike's. The shoe has been responsive, light, and pretty durable. I just hate the price tag. Then again, I think all shoes are overpriced now as I used to be able to buy a nice pair of trainers for $70-80 10 years ago.

Anonymous runner · Oct 3, 2018

30 mpw training for a half marathon came from the ASICS GT-1000 5