Buying clothes online is a gamble on sizing: a medium in one brand can be a large in another, and a size chart that looks precise can still mislead. Returns for clothing are among the highest in online retail, and most are caused by fit, not quality. A few minutes spent measuring yourself and reading charts properly can cut those returns dramatically and save the frustration of waiting for a parcel that does not fit.

Start with three measurements that most size charts use: chest or bust, waist and hips, taken over light clothing with a soft tape measure held snug but not tight. For trousers, add inseam, measured from the inner leg to the ankle, and for tops, consider shoulder width and length if the chart provides them. Write these numbers down and keep them on your phone, because guessing from memory is how wrong sizes happen.

Measure yourself rather than relying on your usual size, because brands cut differently and bodies change. Measure at the same time of day and in the same way each time, since posture and clothing affect the result. If you fall between sizes on a chart, the right choice depends on the garment: structured items like blazers usually need the larger size, while stretchy items can often take the smaller one.

A size chart shows garment measurements or body measurements, and confusing the two is a common mistake. Body measurements tell you what size fits your body, while garment measurements tell you the actual size of the item, including ease, which is the extra room built in for movement. Check which type the chart uses, and look for a note about whether the measurements are in centimetres or inches.

Also check whether the chart is brand-specific or generic. A generic chart copied across many sellers is less reliable than one measured from the actual garment, and some marketplaces display a chart that does not match the seller's product at all. If the chart seems vague or inconsistent with the product photos, message the seller for the actual measurements before ordering.

Reviews are the best source of fit information, but only if you read them the right way. Look for reviewers who mention their height, weight and usual size, and whether the item ran small, true to size or large. A pattern across many reviewers is far more reliable than a single comment, so scan at least ten reviews and note the consensus.

Customer photos are even more useful, because they show the garment on real bodies rather than models. Pay attention to how the fabric drapes, whether it looks tight or loose in the areas that matter to you, and whether reviewers mention shrinkage after washing. If most photos show a different fit from the listing images, trust the customers.

When you are between sizes or buying from a new brand, order the size you think fits best and check the return policy before you pay. Some sellers offer free returns, which makes trying two sizes a reasonable strategy, while others charge return shipping that makes it expensive. Avoid ordering multiple sizes from sellers with costly returns, and never remove tags until you have tried the item properly.

Finally, keep a note of which brands fit you well and in what size, because that record becomes your personal size chart over time. Online clothing shopping gets easier with every successful order, and the buyers who return least are usually those who measure, read and record, rather than those who guess and hope.