How to measure your foot length
Measure standing, not sitting — foot length changes under load
A foot lengthens measurably when weight-bearing compared with sitting relaxed, since the arch flattens slightly and the foot spreads under body weight, so measuring while seated with the foot lifted produces a shorter, less accurate reading than measuring while standing normally — every shoe conversion on this site assumes a standing measurement, and a sitting measurement will systematically undersize you.
Trace the foot rather than trying to hold a tape around it
Stand on a sheet of paper against a wall, with your heel touching the wall and your weight evenly distributed, then have someone trace around the outside of your foot with a pen held vertically — a self-traced outline while balancing is far less accurate than having someone else trace it, or bracing carefully against a wall or chair if measuring alone.
Measure the longest point, which isn't always the big toe
After tracing, measure from the heel's back edge to the longest point of the traced outline — for many people this is the big toe, but for a meaningful number of people the second toe extends slightly further, and the chart conversion needs the true longest point, not an assumption about which toe that is.
Measure both feet — they're rarely perfectly identical
Almost everyone has a small length or width difference between their left and right foot, sometimes enough to sit at the edge of two different shoe sizes — measure both feet and use the larger of the two measurements when converting a size, since a shoe sized to the smaller foot will be uncomfortably tight on the larger one.
Measure in the evening, when feet are at their largest
Feet swell over the course of a day from standing, walking, and simple gravity, typically reaching their largest size by evening — measuring first thing in the morning can understate your true daily foot size by a meaningful margin, so an evening measurement gives a more representative figure for shoes meant to be worn all day.
Wear the socks you'll actually wear with the shoe
If the shoe you're converting a size for will typically be worn with thick socks (winter boots, hiking shoes) measure with those socks on; if it's typically worn barefoot or with thin socks (sandals, dress shoes), measure without thick socks — matching the measurement condition to the actual wearing condition avoids a systematic under- or over-estimate.
Convert your measured length using the shoe chart, not by guessing your usual size
Once you have an accurate standing, evening, both-feet-measured length in centimetres (or inches), use the relevant shoe chart on this site to convert that number into the target country's sizing system directly, rather than starting from your usual home-country shoe size and trying to convert that label — length-based conversion from a real measurement is consistently more reliable than label-to-label conversion.
Re-measure periodically — adult feet do change size over time
Foot length can genuinely increase gradually through adulthood, particularly with pregnancy, significant weight change, or simply aging (ligaments loosening slightly over decades), so a foot-length measurement taken years ago isn't guaranteed to still be accurate — re-measuring every few years, or before a significant international purchase, catches this kind of gradual drift.
Foot width matters as much as length for a genuinely good fit
Length gets you into the right shoe-size ballpark, but width determines whether that length-correct shoe actually feels right across the widest part of your foot — the separate foot-width measure guide on this site covers that second figure in detail, and checking both together, rather than length alone, is what actually predicts a comfortable fit rather than just a technically correct size label.
A ruler works almost as well as a paper trace if you're short on time
If tracing feels impractical, standing with your heel against a wall and placing a rigid ruler flat on the floor against your longest toe, then reading the measurement where that toe ends, gives a nearly equivalent result to the paper-trace method — the key requirement either way is measuring while standing under normal body weight, not the specific tool used to capture the number.
Digital foot scanners at retail stores are a useful cross-check, not a replacement
Many shoe retailers offer an in-store digital foot-scanning device that captures length, width, and sometimes arch shape in seconds — this is a genuinely useful cross-check against a home measurement, particularly for confirming a borderline size call, though it doesn't replace understanding your own measurement well enough to convert sizes confidently when shopping an international brand with no scanner available.
Growing feet in children need remeasuring far more often than adult feet
A child's foot can grow through a full shoe size or more within just a few months during active growth phases, so the evening-measurement and both-feet habits described above matter just as much for children as adults, but the remeasuring interval needs to be much shorter — checking every couple of months during a growth spurt, rather than annually, catches a child who has outgrown their current shoes before it becomes uncomfortable.
Common measuring mistakes that throw the number off
- Measuring with the foot lifted off the ground rather than bearing full weight
- Letting the tracing pen angle inward or outward instead of staying vertical against the foot's edge
- Rounding the final measurement up or down to a "nice" number instead of using the exact reading
- Measuring only one foot and assuming the other matches
- Using an old measurement from months or years ago without checking it's still current
Arch height affects how a length-correct shoe ultimately feels
Two feet sharing an identical length and width can still differ in arch height, which changes how the shoe's insole and structure contact the foot even at a technically correct size — this doesn't change the length measurement itself, but explains why a correctly converted size occasionally still needs an aftermarket insole or a different model within the same brand to feel genuinely comfortable.
Toe box shape changes how much extra room past your longest toe you actually want
A rounded or square toe box gives your longest toe genuine room to sit without pressing the front of the shoe, while a pointed or tapered toe box narrows well before the true tip, so the same converted length can feel noticeably tighter in a pointed style than a rounded one even at an identical size number — for a pointed style, many people find sizing up half a size from their measured conversion the more comfortable choice.
Barefoot versus socked measuring matters far less for length than it does for width or fit
A sock adds only a fraction of a millimetre to your foot's actual length, well under any meaningful rounding threshold, so measuring barefoot is fine for length purposes even if you'll normally wear the eventual shoe with socks on — the sock-thickness consideration described elsewhere on this guide matters much more for how a shoe feels overall than for the raw length figure itself.
Frequently asked questions
I don't have paper or a wall handy — is there another way to get a rough length?
Stand a shoe you already know fits well next to a ruler and measure its interior length from heel cup to toe, then subtract about half an inch for the shoe's own internal taper — it's a rougher estimate than tracing, but usable in a pinch when you need a quick number before an online order closes.
Does a pointed or narrow-toe shoe style need a different size than my measured length suggests?
Often yes — a pointed toe box tapers well ahead of where a rounded one does, so the same measured length can feel tight in a pointed style; sizing up half a size for pointed dress shoes and boots is common practice among people who otherwise wear their measured size everywhere else.
My measured length falls exactly between two sizes on a specific brand's chart — which way should I go?
It depends on the shoe's construction: a leather upper that will stretch slightly with wear tolerates sizing down to the snugger option, while a synthetic or mesh upper with little give is safer sized up, since it won't loosen the way leather does over the first few wears.
Does the shape of my foot's toe line (a longer second toe versus an even, ruler-straight line) change which shoe styles fit best, beyond just the length number?
Yes — a foot where the second toe extends noticeably past the big toe (sometimes called a Greek foot shape) can catch on a shoe whose toe box is tapered specifically for a big-toe-dominant shape, even at the mathematically correct length, so trying the shoe on or checking a brand's stated toe-box shape matters more for this foot shape than for a more even one.
Should I trust the size printed inside an old, well-worn pair over a fresh measurement?
Not fully — leather and fabric uppers stretch and pack out with wear, so a worn shoe's comfortable fit reflects its broken-in shape more than your foot's actual current length, which is why a fresh trace or scan is a more honest starting point than an old favorite's size label.
Is it worth remeasuring before every single online shoe order, or just occasionally?
A yearly check is enough for most adults, plus a remeasure after pregnancy, a significant weight change, or a long injury recovery — foot length doesn't drift quickly outside those specific circumstances, so measuring for every single purchase is more caution than the science actually calls for.
Does the brand of paper or type of pen I use for tracing matter?
Not meaningfully — any firm paper that doesn't shift under your foot and any pen or pencil that makes a clear, thin line works fine; a thick marker can add a millimetre or two of line width that a sharp pencil avoids, which matters only at the margin for a borderline size decision.