New Balance 550 vs Nike Air Force 1 Sizing: Which Size to Buy

Good news if you own one of these and want the other: both the New Balance 550 and the Nike Air Force 1 run about half a size big, so the usual advice is the same for both. Take half a size down from your normal size in each. If you wear a 10 in most Nike shoes, a 9.5 works in the Air Force 1, and a 9.5 works in the 550.

The difference is how they feel at that size. The Air Force 1 is roomier, with a rounder, taller toe box. The 550 is longer than it needs to be but tighter across the forefoot, with a lower, closer fit. That changes who each shoe suits.

Side-by-side sizing summary

• Narrow or average feet: half a size down in both.
• Slightly wide feet: try half down in both. The 550 may need a few wears to soften, and the Air Force 1 is the easier one to wear half down.
• Wide feet: stay true to size in both, especially the 550.
• Between sizes: take the smaller size, unless your feet are on the wide side.
• High volume or high instep: the Air Force 1 is the better choice.
• Narrow, low volume feet: the 550 is the better choice.

For the full story on each shoe, see our individual guides: New Balance 550 sizing and Nike Air Force 1 sizing.

Why both run big, in different ways

The Air Force 1 was designed as a basketball shoe in the early 1980s, and it carries a lot of structure: a thick sole, a tall box at the front and a thick padded collar. The upper has volume, so the foot floats a little at true size. That is the reason for the half size down.

The 550 comes from a 1980s basketball model too, but it sits lower and is built from stiffer leather with a lower toe box. The insole is long, which is where the extra length comes from, and the heel can slide at true size. Half a size down fixes the length. It does not add width, which is why wide-footed wearers stay true to size in the 550.

The width and toe box difference

Air Force 1

The toe box is round, tall and forgiving. Wide and high-volume feet usually fit well, and thick socks or an orthotic do not cause problems. The leather feels soft out of the box, so there is little break-in.

New Balance 550

The toe box is lower and the forefoot is closer, which holds the foot securely. Narrow feet like that. The leather is stiff when new and softens over several wears, and it varies between releases. If the front feels tight on day one, give it time before you decide.

The 550 is also sold in different widths: men's standard is D and women's standard is B, so women with wide feet sometimes find the men's version friendlier. Try the women's pair first if your foot is narrow.

Switching from one to the other

Because both are a half down, the conversion is easy: keep the same number.

• Wear a 9 in the Air Force 1? Try a 9 in the 550.
• Wear a 9 in the 550? Try a 9 in the Air Force 1.

The adjustment is in your foot shape. If you have wide feet and you wear the true size in the Air Force 1, wear the true size in the 550 too, and consider whether the 550 suits you at all. If your feet are narrow and the Air Force 1 feels like a boat, the 550 at a half size down will feel much more secure.

If you are coming from another model, use the same translation. A 9.5 in a true-to-size Nike, such as the Vomero, becomes a 9 in both of these.

Materials and break-in compared

The Air Force 1 is typically a smooth leather shoe, heavier than the 550, with a thicker sole. It feels cushioned and a bit clunky, and it needs little break-in. The 550 sits closer to the ground and feels more connected to the foot, with a lighter, more court-like feel. Its leather is stiff at first, and it softens with wear.

In practice, that means the Air Force 1 feels right sooner. The 550 rewards patience. If you hate breaking in shoes, the Air Force 1 is the easier of the two. If you want a closer fit that molds to your foot, the 550 is the better long-term shoe.

Heel hold and ankle feel

The Air Force 1 has a padded collar that cushions the ankle, and the heel is secure when you size down half a size. At true size, a lot of wearers feel the heel lift on each step. The 550 has a flatter, less padded collar, and the long insole makes its heel slip more noticeable at true size. In both cases, going half a size down fixes most of the movement.

If you still feel a slip after sizing down, the lacing is the next tool. Use the extra eyelet if your pair has one, and avoid lacing so tightly that you pinch the top of the foot, particularly in the lower-volume 550.

Which one should you buy if you are undecided on fit?

Choose by foot shape, not by trend.

1. Wide, thick or high-volume foot: the Air Force 1. You get room at the front and over the instep.
2. Narrow or low-volume foot: the 550. The close fit holds your foot securely and the long insole is less of an issue once you size down.
3. Average foot: either one, so choose on style and on how much break-in you tolerate.
4. You use insoles: the Air Force 1.
5. You want a low, court-like feel: the 550.

None of that is about length, which is the part both shoes share. It is the width, height and stiffness that make the two shoes feel different on the foot.

Trying them on in a store

If you can try both on, do it at the end of the day, with the socks you wear most. Start with the half-size-down pair in each. Stand up, press the front of the shoe and check that there is space for your longest toe, about the width of your thumb. Then walk around and check the heel and the top of the foot.

Pay attention to the top of the toe box in the 550. If you feel pressure on top of your toes, you have high volume and the Air Force 1 is the kinder fit. If you feel the Air Force 1 is swimming, you have a low-volume foot and the 550 is your match.

Insoles and orthotics

If you wear custom insoles, choose the Air Force 1. The interior is deep enough to take an orthotic without squeezing the foot. The 550 is snugger, so an orthotic eats into the already low volume. With an orthotic in the 550, stay at your true size.

Men's and women's conversion

Nike women's sizes run 1.5 larger than men's, so a men's 9 equals a women's 10.5. New Balance does the same. That means the conversion is identical when you move between the two brands. Women's 550s are in B width and men's in D, so try the women's pair first. See our men's to women's guide for more.

Size charts: New Balance and Nike

The charts show how the two brands line up. Notice that the same US size has the same foot length in both. The differences are in UK, EU and the CM (JP) label on the box. For example, a men's US 9 is UK 8.5 and EU 42.5 at New Balance, but UK 8 and EU 42.5 at Nike. Use the brand chart that matches the shoe you are ordering.

The two charts measure the foot differently: Nike puts a men's US 9 at a 26.2 cm foot, New Balance at 27 cm. Most wearers still take the same US number in both, so start from the size you already wear and apply the half-size-down rule. If you need to measure, use our foot measuring guide or the shoe size calculator, and check brand size comparison for other pairs.

Mistakes to avoid

• Going a full size down in either shoe. Both run half a size big, not a full size.
• Assuming wide feet fit the 550. The length is generous, the width is not.
• Judging the 550 on day one. The leather needs time.
• Forgetting socks. A thick sock changes the answer in either shoe.

Our recommendation

Half a size down in both, unless your feet are wide, in which case stay true to size. If you can only pick one for a wide or high-volume foot, pick the Air Force 1. For a narrow foot and a close fit, pick the 550. For all other questions, our New Balance sizing guide and the Nike sizing guide will fill in the gaps.