We are one of the two brands here, so read this with that in mind. We have tried to be straight about where Calvin Klein is the better buy, because for a lot of people it will be. Updated 10 October 2026: Calvin Klein details checked at John Lewis on 8 October 2026, because Calvin Klein's own UK site would not load for us. Prices move, so treat them as a guide.
At a glance
Flissie vs Calvin Klein women's boxers: the quick answer
They are not really the same product. Calvin Klein does not state a leg length for its women's boxer briefs or boyshorts; ours are 6 or 9 inches, stated on the page. That difference decides most of the rest.
- Our pick if your thighs rub: Flissie women's bamboo boxer shorts (we make them): a stated 6 inch leg, in every size from UK 8 to 30 at the same price, £13.50 a pair (£11.50 in a 10 pack), with a 60 day guarantee, full refund, worn or not, and a free size swap on your whole first order.
- Buy Calvin Klein for the brand: its Icon Cotton Modal Boxer Briefs are £28 at John Lewis, with a stitch-free waistband, in XS to XL, and you can try them on in a shop.
- The catch with Calvin Klein: no leg length on the pages we checked, and John Lewis only takes underwear back unopened and unused, unless faulty.
Calvin Klein details from John Lewis on 8 October 2026.
Try Flissie women's bamboo boxer shorts
£13.50 a pair in UK 8 to 30, one price for every size. Buy 6 for £75 (£12.50 a pair) or 10 for £115 (£11.50 a pair), and the 10 pack comes with a free 30 day tub of our perimenopause supplement (worth £29). Free UK delivery on every order, a free size swap on your whole first order, and a 60 day guarantee: full refund, worn or not. We don't know how long we can hold these prices.
Why you can trust this guide
★★★★★ 4.7 out of 5 from 336 reviews of Flissie women's bamboo boxer shorts, and about 2,500 customers since 2021.
- Who wrote it: Phillippa and Matthew, the founders of Flissie. We have designed and sold women's boxer shorts from Derbyshire since 2021.
- Our bias, stated: we make Flissie women's bamboo boxer shorts, one of the two brands here, so read this accordingly. We say where Calvin Klein is the better buy.
- No paid placements: no brand paid to be included, and none of the links earn us money.
- How we compared: leg length, fabric, sizes, price and returns, from John Lewis's Calvin Klein pages and our own product page on 8 October 2026. Calvin Klein's own UK site would not load for us.
"The material is very lightweight and breathable, and the sizing/fit is perfect. Love the colours!" Amalie, United Kingdom, verified buyer, August 2026
Flissie vs Calvin Klein, side by side
Calvin Klein's Icon Cotton Modal Boxer Briefs and Boyshort Knickers at John Lewis, against ours, on 8 October 2026.
| Flissie | Calvin Klein | |
|---|---|---|
| Leg length | 6 or 9 inches | Not stated |
| Main fabric | 95% bamboo viscose, 5% elastane | 53% cotton, 35% modal, 12% elastane (Icon Cotton Modal) |
| Size range | UK 8 to 30 | XS to XL at John Lewis |
| Price per pair | £13.50, or £11.50 in a 10 pack | £28 for the boxer briefs, £25 for the boyshort, at John Lewis |
| Reaches where thighs rub | Yes, that is what it is for | No leg length stated, so check before you buy |
| Range | One style of underwear, two lengths | Full underwear range |
| If you have worn them | 60 days, full refund, worn or not | John Lewis: only if unopened and unused, unless faulty |
| Where to buy | Direct only | Widely stocked, easy to try in person |
On a phone, swipe the table sideways to see every column.
Where Calvin Klein wins
Choice. They make briefs, thongs, bikinis, bralettes and matching sets. We make one style of underwear in two lengths. If you want a range, that is not us.
Availability. You can walk into a department store and try them on. You cannot do that with ours, which is why the size swap on your whole first order is free.
Smaller sizes. Their range at John Lewis starts at XS. Ours starts at a UK 8.
Easier care. Cotton blends are generally more forgiving in the wash than bamboo viscose, which needs a cool wash, no fabric softener and air drying. If low-maintenance matters more than softness, that is a real advantage.
Brand. Fifty years of it. If you like the waistband, that is a legitimate reason to buy.
Where we differ
Leg length. The whole point. If thighs rubbing is your problem, a short-leg boxer brief will not solve it regardless of who made it. Womens boxer briefs at 2 to 4 inches do not reach where thighs touch. Flissie's run 6 to 9 inches.
Fabric. Bamboo viscose is soft from the first wear and moves moisture rather than holding it. Cotton absorbs and holds. Polyester dries fastest but traps heat.
Sizing at the larger end. Flissie's UK 8 to 30 range grades the leg opening and waistband width separately rather than scaling everything up, which is why the leg still sits flat at a 26 or 30.
One price. A UK 30 costs the same as a UK 8.
What we will not claim
Our fabric is not antibacterial and not hypoallergenic. Neither claim is substantiated for viscose made from bamboo, and plenty of brands in this category say otherwise. Our own honest assessment of bamboo underwear goes through it.
We are also not going to score Calvin Klein on sustainability. They are a large business with published reporting, we are two people in Derbyshire, and the comparison would not be meaningful in either direction. What we can tell you about ours is closed-loop production that recovers and reuses the solvent, without carbon disulfide, from FSC certified bamboo, and plant-based packaging that is industrially compostable.
Which should you buy?
If your thighs rub, buy the longer leg. Flissie's or anyone's. Leg length is what puts a smooth layer between your thighs, and the fabric is a secondary question.
If you want a boxer brief or boyshort from a brand you can find on the high street, Calvin Klein is a sensible buy and we would not pretend otherwise.
If you are unsure, Flissie women's bamboo boxer shorts come with a 60 day guarantee (full refund, worn or not) and a free size swap on your whole first order, which is there precisely because you cannot try them on first.
These are very comfortable and cool to wear. Prevents chafing when wearing dresses. They have been a godsend in this hot weather. They wash well too!
Marlene, UK, verified review (reviewer earned a reward for a future purchase)
Flissie vs Calvin Klein: your questions
Are Calvin Klein women's boxers good?
They are well made and widely available, with a stitch-free waistband. The thing to check is the leg length: Calvin Klein does not state one for its women's boxer briefs, and a short leg will not stop thighs rubbing, which is what a lot of people are actually buying boxers to solve.
What is the difference between boxer briefs and boxer shorts for women?
Leg length. Boxer briefs typically run 2 to 4 inches, boxer shorts 6 to 9. Brands use the terms loosely, so check the inseam measurement rather than the name.
Is bamboo better than cotton for underwear?
Not universally. Bamboo viscose is softer from the first wear and handles moisture better. Cotton is cheaper, more forgiving in the wash and lasts longer under rough treatment. We compare them properly in our two-year switch.
How much are Calvin Klein women's boxers in the UK?
At John Lewis on 8 October 2026, Calvin Klein's Icon Cotton Modal Boxer Briefs were £28 for one pair and the Icon Cotton Modal Boyshort Knickers £25, with delivery at £4.50, or free over £50. Flissie women's bamboo boxer shorts (we make them) are £13.50 a pair (£11.50 in a 10 pack), with free UK delivery on every order.
Which is better value?
Depends on how you buy. At John Lewis, Calvin Klein's Icon Cotton Modal Boxer Briefs were £28 a pair on 8 October 2026; Flissie women's bamboo boxer shorts (we make them) are £13.50 a pair (£11.50 in a 10 pack). Per pair we are more expensive than a supermarket multipack, and cheaper than Calvin Klein and most premium brands.
How long is the leg on Calvin Klein women's boxers?
Calvin Klein does not say. Neither John Lewis's page for the Icon Cotton Modal Boxer Briefs nor its boyshort page gives an inseam, and we could not find a Calvin Klein women's boxer short with a stated leg of 4 inches or more on the UK pages we checked on 8 October 2026. Flissie women's bamboo boxer shorts (we make them) have a 6 inch leg in all 8 colours, and a 9 inch in black and pine green.
What sizes do Calvin Klein women's boxers come in?
XS to XL at John Lewis when we checked on 8 October 2026, with no UK size mapping on the page, so Calvin Klein is the one to look at below a UK 8. Flissie women's bamboo boxer shorts (we make them) run from S (UK 8 to 10) to 3XL (UK 28 to 30), at the same price in every size.
What are Calvin Klein women's boxers made of?
The Icon Cotton Modal Boxer Briefs and Boyshort Knickers at John Lewis are 53% cotton, 35% modal and 12% elastane, and the boxer briefs have a 100% cotton gusset. Cotton absorbs and holds moisture. Flissie women's bamboo boxer shorts (we make them) are 95% bamboo viscose and 5% elastane, and want a cool wash and air drying.
Do Calvin Klein women's boxers stop chafing?
Calvin Klein does not publish a leg length for its women's boxer briefs, so check before you buy for chafing. Nothing under about 6 inches reaches the point where most thighs touch, which is why the leg is the specification that matters rather than the fabric or the brand. Flissie women's bamboo boxer shorts (we make them) have a 6 inch leg that reaches where most thighs touch.
Sources
Calvin Klein's own UK site would not load for us, so its details come from John Lewis, checked on 8 October 2026. Prices change often, so check before you buy. We have no commercial relationship with Calvin Klein or John Lewis.
- John Lewis: Calvin Klein Icon Cotton Modal Boxer Briefs
- John Lewis: Calvin Klein Icon Cotton Modal Boyshort Knickers
