Toe room
There should be comfortable room for your toes to move without the foot sliding forward inside the sneaker.
Authentix fit guide
Find the right fit for your rotation.
Use this guide to measure your feet, compare approximate U.S. sizes, and make a more confident choice across sneakers and everyday footwear.
Learn how to measureImportant: The charts below are approximate reference ranges, not a universal Authentix or brand size chart. Sizing, width, shape, and fit can vary between brands and styles. When possible, measure both feet and try the actual sneakers on before making a final decision.
Step one
Measure your feet at home.
A simple measurement can help you find the right starting point. Measure at the end of the day while wearing the socks you would normally wear with your sneakers.
- 01
Stand on a sheet of paper
Place your foot flat on paper with your heel gently touching a wall. Standing captures the foot’s natural length and width.
- 02
Mark the longest point
Mark the back of the heel and the end of the longest toe. The longest toe is not always the big toe.
- 03
Measure both feet
Measure from the heel mark to the longest-toe mark on both feet. Use the longer measurement when comparing the chart.
- 04
Compare, then try on
Use the measurement as a starting point. Your toes should move comfortably and your heel should feel secure while walking.
What you will need
Paper, a pencil, a ruler or measuring tape, and the socks you typically wear with your sneakers.
Step two
Approximate youth sneaker sizes.
Use foot length to find a starting point. If a measurement falls between sizes, begin with the larger size and evaluate the actual sneaker fit.
| Stage | Approx. U.S. size | Approx. foot length | Helpful starting point |
|---|---|---|---|
| Baby / Infant | 0–4 | 3.5–4.75 in | Soft, flexible styles with comfortable room |
| First Walker | 4–6 | 4.75–5.25 in | Secure fit with natural movement |
| Toddler | 5–10 | 5.0–6.5 in | Easy closures and supportive everyday comfort |
| Little Kid | 10.5–3 | 6.5–8.25 in | Room for movement, play, and daily wear |
| Big Kid | 3.5–7 | 8.25–9.75 in | Check width, activity, and secure heel fit |
Foot-length ranges are approximate and provided for orientation only. Actual fit depends on the sneaker’s shape, construction, width, materials, closure, and the wearer’s individual foot.
For adult rotations
Approximate adult reference.
Adult sneaker sizing varies by brand, model, and intended use. Use this chart as a general comparison, then check the product’s own sizing information whenever it is available.
| U.S. size | Approx. foot length | General fit check |
|---|---|---|
| 5–6 | 8.5–9.25 in | Check toe room and width |
| 6.5–8 | 9.25–9.75 in | Heel should feel secure |
| 8.5–10 | 9.75–10.5 in | Allow natural toe movement |
| 10.5–12 | 10.5–11.25 in | Compare width and intended use |
| 12.5–14 | 11.25–11.75 in | Try on with regular socks |
Step three
How should sneakers fit?
The right fit should feel secure without feeling tight. Use these quick checks while standing and walking in the sneakers.
Secure heel
A small amount of movement can be normal, but the heel should not repeatedly slip or lift when walking.
Comfortable width
The sneaker should not pinch the sides of the foot or leave red marks after a short try-on.
Right for the activity
Consider whether the sneakers are for everyday wear, school, training, walking, a release, or a special occasion.
Need a second opinion?
We can help you compare your options.
If you are unsure about a size, width, model, or brand, contact Authentix before visiting. We can help you check current availability and prepare for a more confident shopping experience.
Common questions
Fit guide FAQs.
Should I measure one foot or both feet?
Measure both feet and use the longer measurement as your starting point. It is common for one foot to be slightly longer than the other.
Can I rely on the same size for every sneaker brand?
Not always. Shapes, widths, materials, and sizing systems vary between brands and models. Use measurements as a guide and compare the actual fit whenever possible.
How much extra room should I allow?
You need comfortable room to move, but too much extra space can make walking less secure. The right amount depends on the wearer, the sneaker, and the intended activity.
What should I do if I am between sizes?
Start with the larger size, then evaluate toe room, heel security, and width in the actual sneaker. Also check whether the model is known to fit narrow, wide, small, or large.
Can Authentix help me find a specific size or model?
Product availability and sizes change regularly. Contact Authentix with the brand, model, colorway, or size you are looking for, and we can help check current information.
Authentix Sneaker & Clothing143 Harvard Ave N #A, Claremont, CA 91711
Contact the boutique for current hours and product availability[email protected]
