A size chart predicts your wetsuit size from two numbers: height and weight. It doesn't account for torso length, shoulder width, or where your mass sits. Two swimmers can match those numbers and still need different suits. The chart is a useful starting point. The lake or pool is where the fit proves itself.
Most return confusion starts with a dry-land impulse. You try the suit on at home, feel tightness across the chest and shoulders, and exchange it for the next size up. That size feels better on the carpet and worse in the water. A loose suit lets the warm layer flush out and cold water replace it. You lose thermal protection and body-position support.
Height and Weight Miss Mass Distribution
Height and weight are easy to measure, which is why size charts use them. What they flatten is the distribution of that weight. Your mass can sit in your chest, hips, or legs. Your torso can be long relative to your height. Your shoulders can require more overhead range. Those differences are why two people with the same chart numbers can land in different sizes once they swim.
For women, this is where Femme Fit changes the calculation. Every women's blueseventy wetsuit includes Femme Fit sizing, with pattern adjustments in the bust, torso, wrists, and ankles. The neckline sits lower to reduce chafing. The zipper extends for easier entry, wider hip accommodation, and faster transitions. In 2014, the line expanded to 15 women's sizing options. A height and weight chart flattens exactly the differences Femme Fit was built to address.
A New Wetsuit Should Feel Snug on Dry Land
Swim-specific wetsuits fit closer than surf or scuba suits. The neoprene is designed to let a thin layer of water in. Your body warms that layer, and the suit holds it close. If the suit is loose, warm water flushes out and colder water replaces it. A suit that feels snug on dry land usually settles once you are horizontal in the water and your arms are moving. If it feels roomy in the living room, it will feel baggy in the lake.
Shoulder tightness deserves a second look before you size up. Most new wetsuits need to be worked up into the crotch and pulled fully onto the shoulders before fit can be judged. An improperly donned suit, especially around the shoulders, causes fatigue. Pull the suit higher than feels natural, then assess again. The 2021 Fusion redesign lowered the neckline to improve comfort without losing the watertight seal. That change helps swimmers who feel pressure at the throat.
Between Sizes, Diagnose the Problem
If the chart places you between sizes, don't default to the larger one. A suit that is too long in the torso will bunch, flush water, and reduce body-position support. A suit that is too tight across the chest will restrict breathing. Diagnose where the fit is off first. If the legs and torso fit and only the shoulders feel tight, check your donning. If you can't take a full breath on dry land, that is a real sizing problem.
The 30-Day Test Swim Resolves the Guesswork
blueseventy's return policy exists because a wetsuit can't be properly sized in a bedroom. You have 30 days from the ship date to return or exchange it. The suit must be clean, dry, unmodified, and include the tags and accessories. You can swim in it during that window. The Test Swim policy states that swimming in the suit won't affect your ability to get a refund if the suit comes back clean, dry, and unmodified. This closes the gap between a chart and a real fit decision.
At checkout, you can add $3.28 returns coverage. Without it, you pay the return label. Returns outside the portal incur a 10% restocking fee. Wetsuits are the product this Test Swim policy is built for.
Returns Are for Fit. Warranty Is for Defects.
A size chart problem is a fit issue. A warranty problem is a manufacturing or materials defect. The blueseventy warranty covers the original owner for one year from purchase, with a repair-only remedy. Technical race swimwear is covered for six weeks. It doesn't cover fingernail punctures, heel tears, zipper damage from force, heat or chlorine damage, wear and tear, or any non-swimming use. If you catch a nail in the neoprene while pulling the suit on, that is a repair with neoprene cement, not a return. blueseventy sells neoprene cement for small tears, so a fingernail puncture doesn't end the suit.
How to Use the Size Chart Before You Order
- Start with your current weight, not your goal weight. The suit needs to fit the body you will swim in this season.
- Check the model page for fit notes. Different models use different neoprene grades and panel designs. blueseventy uses Yamamoto neoprene in 38, 39, and 40 cell, and a higher cell number means more flexibility, so a suit with more flexible shoulder panels will feel different from a more durable training suit even in the same size.
- If you are between sizes, narrow it to two options, then let the Test Swim decide.
- If you are choosing a women's suit, use Femme Fit sizing rather than a generic height and weight only.
Find your size in 30 seconds, then take a Test Swim. The chart gets you close. The water gets it right.
