If you have bought a soft, drapey tee shirt in the last ten years, you have almost certainly worn modal fabric without knowing it. It turns up in pyjamas, underwear, loungewear and the kind of top that feels wonderful the moment you put it on. And yet ask most sewists what modal actually is and the answers get vague fast. Is it natural? Is it a brand? Is it just viscose wearing a nicer name?
None of those, as it turns out, and the real answers are more interesting than the marketing. In this guide I will tell you exactly what modal fabric is, why it behaves so much better than ordinary viscose in the wash, how to cut and sew it without stretching it out of shape, and which widely repeated claims about it are simply not true.
What Is Modal Fabric?
Modal is a regenerated cellulose fibre. That means it starts as real plant cellulose, usually wood pulp, which is chemically dissolved into a thick liquid and then pushed through a spinneret to be spun back out as fibre. Textile Exchange describes it as a second generation regenerated cellulosic fibre and a variation of rayon.
So it sits in an awkward middle ground. It is not natural the way cotton or linen are natural, because no plant grows modal. It is not synthetic the way polyester is synthetic, because it is not made from petroleum. The accurate word is semi synthetic, and that is genuinely the right way to think about it.
The technical definition is worth knowing because it explains everything else. The conservation reference CAMEO, run by the Museum of Fine Arts Boston, defines modal as a modified rayon fibre with high tenacity and high wet modulus. Hold on to that phrase, high wet modulus. It is the whole reason modal exists.
Modal Is Not A Brand Name
This one surprises people, and you can check it yourself. Lenzing, the Austrian company most associated with modal, holds a US trademark for LENZING MODAL. But in that very registration, Lenzing disclaimed exclusive rights to the word MODAL on its own. In plain terms, the company that made modal famous formally accepted that it cannot own the word.
So MODAL is generic. LENZING MODAL, MICROMODAL and TENCEL are the trademarks. TENCEL Modal is simply Lenzing’s current brand name for its own modal fibre.
This matters at the cutting table more than you would think. A bolt marked modal tells you the fibre type and nothing whatsoever about who made it or how carefully. A bolt marked TENCEL Modal tells you both.
Why Your Label Probably Says Rayon
Here is a genuinely useful thing for American sewists. Modal is not one of the Federal Trade Commission’s generic fibre names. The FTC’s list of manufactured fibre names in 16 CFR 303.7 includes rayon, and inside the rayon definition it names only lyocell as a permitted alternative. The word modal does not appear in the regulation at all.
That is why you will often pick up a garment that feels exactly like modal and find rayon on the content label. The two are not in conflict. Modal is a type of rayon, and rayon is the name the regulation recognises. If you would like the full picture on that family, our guide to viscose and rayon covers where each name comes from.
How Modal Is Made, And Why It Beats Viscose
Modal and viscose start down the same road. Wood pulp is steeped in sodium hydroxide, then reacted with carbon disulfide in a step called xanthation, which produces a deep orange, treacle thick solution. That solution is what gets spun.
Lenzing’s modal comes from beech wood. Do not assume that of every modal, though, because generic modal is variously reported as birch and other hardwoods, and Lenzing’s own current page says only that the wood is from certified or controlled sources.
The parting of the ways comes at the spinning bath. Modal uses a different spinning solution and a modified coagulation bath so the fibre regenerates more slowly and can be stretched further while it is still soft. That stretching lines the cellulose chains up neatly, and that alignment is what gives modal its strength.
The numbers make the difference obvious. Ordinary viscose rayon has a dry tenacity of roughly 1.5 to 2.4 grams per denier and a wet tenacity of about 0.7 to 1.2, which is close to losing half its strength the moment it gets wet. Modal comes in at 3 to 5 grams per denier. CAMEO puts the practical result plainly: modal fibres do not shrink or get pulled out of shape when wet the way many rayons do.
Wet modulus simply means resistance to stretching under load while wet. It is why an old rayon top can come out of the wash a size longer and sadder, and a modal one usually does not. Anyone who has ever tried to rescue a stretched rayon knit will understand immediately why this was worth inventing.
Is Modal Better Than Cotton?
Different, not better, and the honest answer depends on what you are making.
Modal wins on drape and next to skin comfort. It is more absorbent than cotton. The moisture regain figures put the rayon family at roughly 11.5 to 12.5 percent against cotton at 7 to 11 percent, which is a real difference you can feel on a warm day. You will see the claim that modal absorbs fifty percent more moisture than cotton repeated all over the internet. I could not trace it to any current Lenzing document, so I am not going to repeat it as fact.
Cotton wins on heat tolerance and forgiveness. Under the international care symbol system, cotton and linen get the three dot iron, up to 200 degrees Celsius. Viscose family fibres get two dots, 150 degrees. That is a serious gap when you are pressing a collar, and it is the single most common way people ruin modal.
The fairest summary: cotton is the more forgiving fibre to handle and press, modal is the better drape and better next to skin fibre.
Is Modal The Same As Polyester?
No, and they are not even in the same chemical family. Modal is regenerated cellulose made from plants. Polyester is a long chain polymer made from petrochemicals.
The difference you will actually notice is moisture. Rayon family fibres sit around 11.5 to 12.5 percent moisture regain. Polyester sits at 0.4 to 0.8 percent. That is the entire reason modal feels cool and absorbent against the skin and polyester does not.
The honest overlap is that both are manufactured fibres, extruded through a spinneret. Neither is natural in the way cotton is.
Is Modal Fabric Cotton?
Not at all. Modal contains no cotton whatsoever.
Two things drive this question. First, cotton and modal are both cellulose at the molecular level, so they take dye similarly and feel like relatives. Second, and more practically, a great deal of the modal a home sewist actually buys is a cotton modal blend. A typical bolt might be 57.5 percent cotton, 37.5 percent modal and 5 percent spandex. So cotton modal genuinely is part cotton. Modal on its own never is.
How To Sew With Modal
Modal reaches most of us as a knit, usually a single jersey, sometimes blended with cotton and a little spandex. Woven modal exists and behaves like rayon challis, but the knit is what you will meet at the fabric shop.
Needles
For modal jersey, reach for a stretch needle in 75/11 first, particularly if there is any spandex in the blend. Schmetz makes the distinction clearly: the stretch needle has a shorter, narrower eye and a deeper scarf, which is what prevents skipped stitches on elastic fibres. A jersey ball point is the alternative, and Schmetz says the two are sometimes but not always interchangeable. Test on a scrap.
For woven modal, go finer and sharper. A brand new 70/10 microtex is the usual recommendation, and some sewists prefer 65/9. New is the operative word. A dull needle snags this fabric.
Thread
This is where good sources genuinely disagree, so let me give you the reconciliation rather than pick a side.
For woven modal, Threads and Seamwork both warn against polyester thread, because thread stronger than the cloth can shred the seam under stress. For modal knits, extension service guidance goes the other way and recommends a fine polyester, precisely because cotton thread does not stretch.
Both are right within their own fabric. In a stable woven, thread stronger than the cloth is a liability. In a stretch knit, thread that will not stretch is the liability. So: cotton or fine cotton wrapped for woven modal, fine polyester for modal knits.
Stitch And Feed
A narrow zigzag or a lightning stitch on knits, so the seam can give. On long woven seams, a very narrow zigzag around 0.5mm wide and 2.5mm long lets the seam relax with the fabric instead of fighting it.
If your seams come out wavy, reduce the presser foot pressure. Soft cellulosic jerseys need a lighter touch than stable knits. A walking foot also helps enormously by feeding both layers evenly.
If the machine tries to eat the leading edge of a seam, which it will, you have three good options: start a little way in and reverse back to the edge, begin with a long straight stitch before switching, or lay a strip of tissue paper underneath and tear it away afterwards.
Pressing, And This Is The Big One
Two dots. One hundred and fifty degrees Celsius, maximum. Viscose rayon starts losing strength above roughly 300 degrees Fahrenheit and begins to decompose between 350 and 400. Set your iron for cotton and you will scorch, shine or weaken it.
Technique matters as much as temperature. Press, do not iron: lift and set the iron down rather than sliding it about, because sliding stretches the fabric. Use a press cloth, always, because overpressing this fibre produces shine you cannot undo.
How To Care For Modal
Prewash. Always, and in exactly the way you intend to wash the finished garment. You will read in a lot of places that modal does not shrink. That is overstated. Modal is more dimensionally stable than plain viscose, which is a real and measurable advantage, but knits in general shrink more readily than wovens, and telling a sewist not to prewash is bad advice that will cost somebody a well fitted top.
After that it is easy to live with. Cool or warm wash, similar colours together, no bleach. Sources split on tumble drying: brand care guides say hang dry, while fabric retailers and pattern companies accept a low tumble. The technical literature is on the side of a low tumble being fine, precisely because of that high wet modulus. Skip the fabric softener, which does modal no favours.
The Environmental Picture, Honestly
Modal gets sold as an eco fabric. The truth is more mixed, and I would rather you had it straight.
Modal is made by the viscose route, which means carbon disulfide. It is not a closed loop process. That is lyocell, which recovers about 99.8 percent of its solvent. Reported chemical recovery for Lenzing modal is up to 95 percent, and note that up to is a ceiling rather than an average. The viscose sector as a whole has documented problems: the Changing Markets Foundation’s Dirty Fashion investigation recorded untreated wastewater being dumped into local waterways.
On forestry there is genuine good news. Canopy’s Hot Button Report, which assesses most of the world’s producers of these fibres, has Lenzing tied for the top spot, and the share of assessed capacity rated low risk has climbed from zero percent in 2016 to around 54 percent in 2025. The flip side of that same number is that roughly half of global capacity is still not rated low risk.
So the fair summary is this. Modal from a named, certified producer is meaningfully better than commodity viscose on both forestry and chemical recovery, and Lenzing’s branded fibre is certified biodegradable. Modal is also not organic, and cannot be, because GOTS certifies natural fibres rather than regenerated ones. And unbranded modal of unknown origin carries real, documented risk. Saying modal is eco friendly without naming the producer is not a claim anyone can support.
Best Sewing Projects Using Modal
Modal’s whole character is fluid drape, so work with that rather than against it.
Drapey tee shirts and layering tops. A mid weight modal blend jersey at around 200 grams per square metre is the sweet spot, and the easiest place to start.
Loungewear, pyjamas and nightgowns. High absorbency plus real softness makes this modal’s natural home.
Knit dresses and skirts cut to skim rather than to fit closely, because the drape is the point.
Underwear and camisoles, especially in the finer micro modal weights.
Cardigans and wraps in modal French terry around 270 grams, which is far easier to handle than the light stuff if you are new to this fibre.
What not to make: anything needing structure, sharp tailoring or a crisp edge. And be careful with heavy fusible interfacing, both because of that low iron ceiling and because fusibles have a reputation for lifting off cellulosics after a few washes.
When you are ready to cut into some, there are plenty of makes on our free sewing patterns page that suit a soft modal jersey beautifully, and more in the pattern store.
Tips For Sewing With Modal
Tip 1: Never Let It Hang While You Cut
If a length of modal hangs off the edge of the table, its own weight will stretch it and you will cut a distorted piece without ever noticing. Support the whole length on the table or a chair. Roll cut pieces rather than lifting them.
Tip 2: Hang The Garment Overnight Before You Hem
The rayon family settles. Hang the finished garment for twenty four hours, then level and hem it. Skip this and you will get a hem that dips at the back a week later.
Tip 3: Tame The Curling Edge
Single jersey curls, and that is the knit structure rather than the fibre. Pattern weights over the rolling edge, a light spray starch on the edge only, or serging the edge to add a little weight all help. Not every modal blend curls, so test a scrap before you assume.
Tip 4: Stabilise The Seams That Take Strain
Shoulder seams and necklines will grow without help. Narrow twill tape, clear elastic or stay tape stitched into the seam keeps them honest without adding bulk.
Tip 5: Change The Needle Every Project
Modal snags. A needle that is merely slightly blunt will pull threads and leave pinholes that show. Needles are cheap and a ruined front bodice is not.
Claims About Modal You Can Safely Ignore
- It does not shrink. Overstated. Prewash anyway.
- It does not pill. Widely repeated, and I could find no test data either way.
- It never creases. No evidence. Cellulosic fibres crease.
- It absorbs fifty percent more water than cotton. Untraceable to any current manufacturer source. It is more absorbent, which is the honest version.
- It is a closed loop fibre. That is lyocell, not modal.
- Lenzing is the only company making modal. True around 1990, not true now.
- It is just viscose with a fancy name. The wet strength difference is real and measurable.
Related Fabric Guides
If you enjoy knowing what you are sewing, you may also like our guides to ponte, the knit that behaves like a woven, minky, poplin, seersucker, boucle and slub cotton. If you would rather work by hand for a while, our essential hand sewing stitches will see you through most repairs.
Modal is one of the nicest things you can put through a sewing machine once you understand it. Keep the iron cool, support it while you cut, let it hang before you hem, and it will reward you with tops and loungewear you reach for constantly. Buy it from a named producer if you can, and you will know what you are getting.
Have you sewn with modal yet? Tell me in the comments how it behaved for you, and whether you found a blend you loved.
Some links above are Amazon affiliate links. As an Amazon Associate, So Sew Easy earns from qualifying purchases at no cost to you.
Thanks so much for your comment!
It would be great if you could share this post with your friends!