Write down your foot measurements first
Start with a repeatable measurement rather than the size of your most recent pair. Measure both feet on a hard, flat surface and record the units. For the measurement method, follow the instructions supplied with the chart you plan to use. Keep the socks you intend to wear in mind, particularly when comparing winter boots.
Nike’s foot-length instructions use the longer of the two measured feet for its chart. adidas also explains measuring both feet and checking width. These are references for a measurement process; neither brand’s chart establishes the sizing of a different marketplace listing.
Find out what each centimetre number describes
A centimetre value can describe a person’s foot, a removable insole, an outside sole or a printed size label. Those are different measurements. Nike explicitly distinguishes its CM/JP label from foot length. Do not assume that a similar-looking CM column on another listing has the same meaning.
Before comparing rows, ask whether the chart describes the exact selected model and whether it is for adults, children or a particular sizing range. A product photograph and a generic conversion chart can belong to different variants.
| Field | What it describes | Question to resolve |
|---|---|---|
| Foot length | Heel-to-toe measurement of the foot | Which measuring method does this chart require? |
| Insole length | A measurement of an insert | Is the insert removable, and how was it measured? |
| Outsole length | The outside bottom of a shoe | Why is this being used instead of the fit chart? |
| CM / JP label | A size marking | How does this label map to this model’s chart? |
Work through a chart mismatch
Consider a hypothetical shortlist: you record a 26.4 cm foot measurement, while one seller gives only an EU size and another lists a 27.0 cm insole. The second number is not automatically a 0.6 cm fit allowance. The two measurements refer to different things, and the shape and internal space are still unknown.
The useful next step is to request the model’s foot-length guidance and width information. Keep the listing unresolved until you can compare the same type of measurement. This example deliberately does not prescribe a size or a universal allowance.
Check the fit questions that length misses
Record your questions about width, toe shape and the space over the top of the foot. For boots, add the opening, fastening and room for the socks you plan to use. Moving to a larger size can alter length without resolving the shape you need.
A review becomes more useful when it identifies the exact model, size and relevant measurements. A statement such as true to size without that context gives you little to compare. Treat a photograph of a shoe on someone else as styling context rather than a measurement.
Ask for photos that answer the remaining question
For a potential pair, compare the selected colour and size with the available label, side, heel and sole views. If a measurement photograph is provided, establish which dimension it shows and where the ruler begins and ends.
Keep visible evidence separate from comfort, durability or authenticity claims. A useful photo can answer a shape or label question while leaving those other questions unresolved. Do not convert a higher photo count into a fit recommendation.
Keep a footwear comparison record
For each candidate, save the exact URL, size range, chosen size, chart type, units, relevant foot measurements and the question still open. Reopen the listing before continuing because a saved product identifier does not preserve its current options.
Then compare the complete cost for your chosen variant and packing arrangement. A shoe box is part of the parcel decision; product sizing and packed-box dimensions belong in different parts of your notes.
See the comparison behind the steps
See why foot length, insole length and CM labels cannot be interchanged.
Why shoe labels and foot length differPut your shortlist together.
Browse the matching product categories, compare approximate prices and check the reported references.
Browse the spreadsheet