Midsole alignment and height
Whether the midsole runs true to the upper on both shoes, and whether both midsoles carry the same height along their length.
The reading sequence
3 steps, starting at structural defects and running to stand both shoes side by side and shoot from behind. Evidence on this point is read at E1, and 1 of the 3 steps carries a condition that ends the assessment outright.
Trace the midsole line from heel to toe
Check that the midsole edge follows the upper without stepping in or out along its length.
Evidence: E1 — a lateral photo of each shoe at eye level with the sole line
- The midsole edge runs parallel to the upper from heel to toe on both shoes.
- The painted or moulded line on the midsole is not crossed by the upper anywhere.
- A small inward step near the heel, under 2 mm, with the rest of the line true.
- The upper overhangs the midsole, or the midsole protrudes past the upper, by more than 2 mm at any point.
- The midsole line wanders, so the shoe looks twisted when viewed from behind.
Measure the midsole at three fixed points
Establish whether both shoes share the same midsole height at the heel, the arch and the forefoot.
Evidence: E1 — three side-on photos per shoe with a ruler held against the midsole
- Heel, arch and forefoot heights differ by 2 mm or less between the two shoes.
- The ruler is held vertically against the midsole in all six photos.
- A 3 to 4 mm difference at one point, with the other two points matching.
- Any point differs by 5 mm or more, which changes how the shoe stands and wears.
- The ruler is absent or held at an angle in the photos, so no measurement can be read.
Stand both shoes side by side and shoot from behind
See whether the pair stands level, which is the check that catches a height difference the individual photos hide.
Evidence: E1 — one rear photo of both shoes together on a flat surface
- Both heels meet the surface and the collars sit at the same height.
- The gap under each arch is the same shape.
- A heel gap on one side of under 2 mm that closes when the shoe is pressed.
- One heel lifts off the surface, or the pair leans to one side.
- The collars differ in height by more than 4 mm in the rear view.
Why the thresholds sit where they do
Midsole errors survive shipping and cannot be corrected at home, which is why they sit in the structural group and are read before any surface question. Individual photos are unreliable here because a slight camera tilt makes a level midsole look sloped, and a level midsole photographed from above hides a height difference completely. The sequence therefore uses a line trace, a three-point measurement, and a rear view of the pair together. The rear view is the step that most often overturns a conclusion reached from the first two, which is why it is placed last and not merged into step 2.
Common misreads
2 pairs recorded for this point. Each runs in both directions: 1 finding that looks worse than it is, and 1 that looks better.
- looks like Return actually Query
A midsole that looks sloped in a single lateral photo. Camera tilt of a few degrees reads as a slope. The rear view of both shoes settles it.
- looks like Pass actually Return
Two individually correct lateral photos with no ruler. Height differences of 5 mm are invisible without a reference held in frame.
Check this point against what you were sent
Insufficient evidence
Nothing decided on midsole alignment and height yet: 0 of 3 steps have been read.
0 of 3 steps judged
| Step | Reading | Evidence | Stop met |
|---|---|---|---|
| 1. Trace the midsole line from heel to toeneeds E1 | The upper overhangs the midsole along a stretch rather than at a single point. That is a lasting error, not a finishing one. | ||
| 2. Measure the midsole at three fixed pointsneeds E1 | — | ||
| 3. Stand both shoes side by side and shoot from behindneeds E1 | — |
Sources and checks
- Public community thread — Pair comparisons where a height difference was disputedn=47
- Editor analysis — 2 mm and 5 mm tolerance bands set from repeated measurement of the same pairno sample
Last checked · next review due · status current.
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