Clothes and footwear
Measure sandals and slides before buying online
A familiar shoe size is only a starting point for an open sandal or slide. The shape of the footbed, its width and the position of the straps can change how the same labelled size feels.
Measure before ordering and keep the seller’s return conditions available. This guide helps compare fit information; it does not diagnose foot conditions or replace professional fitting advice.
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Use the brand’s current instructions
Find the measurement guide for the exact product range and market. Check whether it asks for foot length, width or a printable outline. If printing a template, verify its scale with a ruler before relying on the result.
Measure both feet as the manufacturer directs. Birkenstock’s fit tool asks for the length and width of each foot, reflecting why a single length measurement can miss a width difference.
Compare more than the size number
Check the width option, footbed outline and where the straps sit. A slide without an adjustable strap may leave less scope to adapt the fit than a different design. Ask the retailer for missing measurements before ordering.
Do not transfer a brand-specific size recommendation to another make. Compare its own chart and model notes, particularly if the seller offers both narrow and regular versions.
Try them without losing return options
Read the seller’s try-on and returns instructions before removing labels or wearing the footwear outside. Check the fit on both feet and whether the straps can be adjusted as intended.
If a toe or heel overhangs the usable footbed, straps create persistent pressure, or the pair feels unstable, reconsider the size or style. Follow the brand’s fit guidance rather than assuming a different shape will become suitable with wear.
Keep the useful comparison
Record the model, width, measurements and the reason for keeping or returning it. Those notes are more useful for a future order than simply recording the size number.
The longer footbed and strap guide below covers the design comparison. If you have pain, a medical foot condition or specific support needs, seek advice from an appropriate clinician or qualified fitter.
Your next steps
- Measure both feet using the exact brand’s guide.
- Check the width and strap adjustment as well as length.
- Keep packaging and follow the retailer’s try-on conditions.
Sources and further help
Each source below shows its recorded consultation date. Provider terms and services can change; check your exact booking, product or university service.
- Birkenstock UK: fit guide calculator · Consulted
- Birkenstock: printable foot measurement instructions · Consulted