Sizing, Model and Fit

What size should I get?

Please use the ShoeFitr application (located on each shoe page) in order to help with an accurate size estimate.

How do I know if my shoes fit properly?

The proper fit in your Newtons should give you about a thumb's width from the end of your longest toe to the end of the shoes. This should ensure that the raised lugs on the midfoot are fairly centered under the ball of your foot to allow you to hit your sweet spot on every stride!

Is it okay to use orthotics with Newtons?

Yes. Simply remove the insert that comes with the shoes and replace it with your over-the-counter insert or custom orthotic.

For custom orthotic information, please contact the Newton Running Lab at 303.494.0321

Do you have a wide model?

Yes, the Sir Isaac Wide Guidance Trainer accommodates a 2E width foot. However, all of our shoes have a more anatomical fit with a roomy toe box and a flexible mesh upper that tends to work well for runners with a wider foot.

Shoe Facts and Details

What should my wear pattern look like?

Newton Running shoes are designed to show wear from the outside-in and your unique wear pattern can give you great feedback about your form and technique. Flip over your shoes and take a look!

Ideally, you should see most of the wear centered on the front third of the lugs under the ball of your foot and  little friction wear on the heel or toe of the shoes.

For more information on your wear patterns, check out our customer corner video

How many miles will my Newtons last?

All Newton Running shoe models other than the MV3 and Tri Racer have an average lifespan of 350-500 miles (500-800 km).  The MVand Tri Racer are racing flats with a 150-200 mile lifespan.

If you'don't keep track of your mileage, you can usually tell when you need to retire your current pair based on how they feel - once your Newton shoes are no longer giving you the same "pop" they once were, it is probably time for a new pair.

How do I clean my Newton shoes?

We recommend hand washing your shoes using warm water, a mild detergent, and an old toothbrush. Be sure to let the shoes air dry as well.  The insoles should also be cleaned by hand, or if they get past the point of cleaning, simply replace them with an over-the-counter replacement insole such as Spenco.  

Where are Newtons made?

Newton Running is a Boulder, CO based company – all the design, research, and wear testing is done here locally, and our shoes are produced overseas in our factory in China.  

Adjusting to the Shoes

Can I rotate my Newtons with my old shoes?

As you transition to your Newtons you can continue to rotate them with your more traditional running shoes. When starting out, we recommend using your Newtons for 15-20 minutes at a time and your other shoes for the rest of the mileage you want to log as this will help you adjust to the more level platform and unique technology in our shoes. You'll notice that the more you're in your Newtons, the less you will want to be in your old shoes!


My calves are sore. Are yours?

Running with a more natural running technique engages the Plantar Fascia, Achilles tendon and calf with every foot strike. These muscles and tendons work very efficiently in unison but they are tiny and, therefore, susceptible to fatigue. Some slight soreness as you adjust to your Newtons is totally normal and nothing to worry about - it just takes some time to build strength and lengthen those muscles and tendons so be patient and take your time breaking in your shoes.

How long will it take to adjust to my Newtons?

Every runner is a little bit different in how long it will take them to adjust to their Newtons as it depends on a lot of factors - for somer runners it takes a week and for others it may take months. We recommend starting with 10-15 minutes of running in the shoes and building up gradually from there. Click here for more information about the transition.

Running Form & How to use Newton Shoes

Can I run long in Newtons?

Definitely!  Your Newton shoes are built to take whatever distance you want to log in them, whether it's 5 km or 500 km.  The only models that are built specifically for shorter distances are our racing flats the MVand Tri Racer.

Can I run in both my Newtons and traditional running shoes?

As you're adapting to your Newtons, we recommend that you switch back and forth with your traditional shoes. However, once you have completely adjusted to your Newtons, they are designed to be your full-time training and racing shoes.  

How do I run midfoot downhill?

Running downhill with a midfoot strike takes a bit of time to master.  A confident, rapid leg turnover will allow you to stay on the midfoot while continuing to accelerate on the downhill. Keep your feet level to the ground rather than pointing your toes down and stabbing the ground or overstriding and braking with your heel. Watch a demontration here

Good resources and information on Natural Form Running

Newton Running Cofounder Danny Abshire’s book Natural Running is an outstanding resource for people interested in learning more about running efficiency and form. Other resources include:


Purchasing, Exchanges & Returns

I'm getting an error message when I place my order. Why?

This is usually due to the billing address not matching what the bank has on file for your credit card.  You can change that address and try again, or you can simply contact Customer Service at 303.442.1113 to place your order over the phone.

There are multiple authorizations against my credit card. Why?

When you place an order, we authorize your credit card to confirm it is valid and that there are sufficient funds available for your purchase. 

An authorization does NOT charge your card at that time, but some banks may hold the authorization for the purchase amount on a customer's card for up to 7-10 business days.  It will appear on your statement as a 'pending charge' and is usually for a dollar more than the original purchase amount. 

We do not charge your credit card until your item(s) have been shipped.

If your order has been split into multiple shipments, we will only collect payment on the portion of your order that has shipped. 

Please review your shipment notification email for details on the amount actually charged to your credit card.

If you wish to remove the authorization, please contact your credit card's issuing bank.  

How do I find my tracking number?

Once your order has shipped, you will receive an email confirmation.  This email will include your UPS tracking number and a link to the UPS tracking website. 

How do I exchange my shoes?

Return authorizations are required for all exchanges. Pleease contact Newton Running Customer Service at or 303-442-1113 within 30 days of your purchase to exchange your Newton shoes.

How do I return my shoes?

Return authorizations are required for all returns. Please contact Newton Running Customer Service at or 303-442-1113 within 30 days of your purchase to either exchange your Newton shoes or return them for a refund.

Do you have a guarantee?

We offer all our customers in the US and Canada the same 30-day, no-questions-asked return and exchange policy on all shoe purchases. 

Is there a retailer near me?

Our retail and international distribution partners can be found on the Retail Locator page.

Global Responsibility

What does Newton Running do to improve the world?

Newton Running cofounders Jerry Lee and Danny Abshire created the company with the desire to give back and improve our world. Visit our Global Responsibility page to learn more.

What are Newton's policies regarding responsible production and human rights protections?

The Newton Running Human Rights Production Standards reflect the relevant covenants of the International Labor Organization, input from human rights organizations and academia, and our own experience. In developing this policy, we sought to use standards that are fair, appropriate to diverse cultures and that encourage workers to take pride in their work.


Newton Running will seek business partners who do not discriminate in hiring and employment practices, and who make decisions about hiring, salary, benefits, training opportunities, work assignments, advancement, discipline, termination and retirement solely on the basis of a person disability to do the job.

Working Hours/Overtime

Workers shall not be required to work more than 60 hours per week, including overtime, except in extraordinary circumstances. In countries where the maximum work week is less, such local standard shall apply. Workers shall be entitled to at least one day off in every seven-day period. Adherence to this Newton Running Standard is a sign that factory management efficiently organizes its production planning and workflow.

No Forced Or Compulsory Labor

No factory making Newton Running products shall use forced or other compulsory labor, including labor that is required as a means of political coercion or as punishment for holding or for peacefully expressing political views. Employers will maintain sufficient hiring and employment records to demonstrate and verify compliance with this provision. Newton Running will not purchase materials produced by any form of compulsory labor and will terminate business relationships with any sources found to utilize such labor.

Fair Wages And Benefits

Newton Running will seek business partners committed to the betterment of wage and benefit levels to the extent appropriate in light of national practices and conditions. Newton Running  will not select business partners who pay less than the minimum wage required by applicable law or who pay less than the prevailing local industry wage.

No Child Labor

Newton Running seeks business partners who do not use child labor. The term "child" refers to a person who is younger than 15, or younger than the age for completing compulsory education in the country of manufacture, whichever is higher.

Freedom Of Association

Newton Running will seek business partners that share its commitment to the right of employees to establish and join organizations of their own choosing. Newton Running  recognizes and respects the right of all employees to organize and bargain collectively.


Newton Running will seek business partners that treat their employees with respect and dignity. No worker will be subject to any physical, sexual, psychological, or verbal harassment or abuse.

Safe And Healthy Work Environment

Newton Running will seek business partners that strive to assure employees a safe and healthy workplace and that do not expose workers to hazardous conditions.

Non-Retaliation Policy

Factories must publicize and enforce a non-retaliation policy that permits factory workers to express their concerns about workplace conditions without fear of retribution or losing their jobs. Workers should be able to speak without fear directly to factory management or Newton Running representatives.

Environmental Footprint

Newton Running will work with our partner suppliers to promote positive environmental awareness and responsible practices.

Education, Events & Expos

Are there any upcoming events in my hometown that highlight Newton Running?

We're on the road all the time! Come see us at a running or triathlon expo, form clinic, or educational symposium.

Corporate Information & Programs

How can I reach someone at Newton Running?

Visit our Contact Us page for more information on how to call or email us.

Do you offer Active Duty Pricing?

We do!  Newton Running is proud to support our active duty Military, Police, and Firefighters by offering a 20% discount and free shipping on all orders placed through our website. Are you active duty?  Apply Now!

Do any professional athletes run in Newton Running Shoes?

Yes! Newton Running’s pro-team includes many world champions, ultramarathoners and triathletes. Visit our Athletes page to learn more.

Job opportunities?

In the event that job openings become available with Newton Running, you will see them posted under the Careers section of our website.


In the case that job postings become available with Newton Running, you will see them listed in the [Community][LW1] section of our website.

 [LW1]Link to Careers page.