When it comes to sewing kids clothing, two fabrics come up again and again: cotton lycra and French terry. Both are knit fabrics, both are popular for children's garments, and both print beautifully. But they behave quite differently on the cutting table and on a growing body, so picking the right one genuinely matters. Whether you are planning a batch of leggings, a cosy hoodie, or a wardrobe full of play-ready basics, understanding the difference between cotton lycra and French terry for kids clothing will save you from costly fabric regrets.
What is cotton lycra?
Cotton lycra (sometimes called cotton spandex or jersey knit with lycra) is a smooth, single-knit fabric made from a blend of cotton and a small percentage of elastane, usually somewhere between 5% and 10%. That elastane content is what gives it its signature four-way stretch. The fabric is lightweight, close-fitting, and recovers its shape well after washing and wearing, which makes it ideal for garments that need to move with a child rather than restrict them.
Cotton lycra is the go-to choice for leggings, fitted tee-shirts, bodysuits, bike shorts, and swimwear-style activewear. It sits close to the body without feeling tight, and because of its smooth surface, it takes digital prints with exceptional clarity. Fine details, photographic designs, and bold colour blocks all pop on a quality cotton lycra base. If you are after vibrant, detailed prints on a garment your kids will actually want to wear every day, cotton lycra is hard to beat.
What is French terry?
French terry is a looped-back knit fabric with a smooth face and a soft, looped interior. Unlike cotton lycra, it has more body and weight to it, which gives finished garments a more structured, relaxed silhouette. It has a moderate two-way stretch (mostly horizontal), so it is comfortable without being truly form-fitting.
The looped interior is what sets French terry apart. Those loops trap air and provide a layer of warmth without the full bulk of fleece, making French terry an excellent choice for cooler-weather kids clothing. Think pullover hoodies, sweatshirts, track pants, shorts with a relaxed fit, and casual lounge sets. Because of its textured reverse side, prints sit on the face of the fabric and can appear slightly softer in finish compared to cotton lycra, but the results are still striking, especially for designs with bold shapes and strong colour contrasts.
Key differences at a glance
- Stretch: Cotton lycra has four-way stretch with excellent recovery. French terry has two-way stretch and is less clingy overall.
- Weight: French terry is noticeably heavier and more substantial. Cotton lycra is lighter and more fluid.
- Warmth: French terry's looped back makes it warmer, suited to cooler seasons. Cotton lycra is a year-round fabric but performs best in spring and summer.
- Finish: Cotton lycra has a smooth, sleek surface. French terry has a smooth face but a soft, looped interior.
- Print quality: Both print well via digital printing methods. Cotton lycra delivers sharper fine detail; French terry suits bolder, graphic-style designs.
- Best garments: Cotton lycra excels in leggings, fitted tees, and activewear. French terry shines in hoodies, sweatpants, and casual separates.
Which fabric is better for active kids?
For high-movement, active wear, cotton lycra wins on performance. Its four-way stretch means it moves in every direction without pulling or bunching, and it recovers its shape quickly after a day of running, climbing, and rolling around. Because it sits closer to the body, there are no loose sections to catch on playground equipment. It is also quicker-drying than French terry, which is a bonus when kids are working up a sweat.
French terry is not a poor choice for active kids by any means, but its weight and structure mean it is better suited to casual activity rather than full-on sport. A French terry track pant is great for school runs, park visits, and after-school play. For gymnastics, dance, or serious sport, cotton lycra is the more practical pick.
Sewing with cotton lycra vs French terry
Both fabrics are beginner-friendly as knits go, but they do have different personalities on the machine. Cotton lycra's lightweight stretch means you will want to use a ballpoint or stretch needle and a small amount of tension adjustment to avoid wavy seams. A serger (overlocker) gives the neatest finish, but a stretch stitch on a regular sewing machine works well too. Because the fabric is thin, seam allowances sit flat and bulk is rarely an issue.
French terry is more forgiving to cut and sew because its weight keeps it stable on the table. It does not slip around as much as lighter knits, and the seams have a nice, clean appearance. The main consideration is bulk at hems and cuffs. When sewing hoodies or joggers, you may want to trim seam allowances and press carefully to avoid thick, stiff seams around the waist and cuffs. For more guidance on caring for your finished garments once they are made, the post on how to wash and care for digital printed fabric covers everything you need to keep prints looking vivid through repeated washes.
How they compare for digital printed designs
At Fabric by TrishaMakes, both cotton lycra and French terry are available as digitally printed fabrics through preorder and ready-to-ship options. Digital printing produces rich, detailed images directly onto the fabric, and the choice of base fabric changes how the finished print reads.
On cotton lycra, prints have a crisp, almost photographic quality. Fine lines, gradients, and intricate patterns come through clearly because the smooth surface gives the ink an even base to sit on. This makes cotton lycra the better choice when you are working with a complex or detailed design.
On French terry, the print sits on the fabric face and still looks vibrant and sharp, but very fine detail can appear slightly softer given the texture of the base. Bold, graphic designs, character prints, and large-scale patterns tend to look absolutely striking on French terry. If you are choosing a design from the latest fabric design trends, consider whether the design relies on fine detail (go cotton lycra) or bold shapes and colour (French terry will shine).
Choosing the right fabric for your project
The simplest way to decide is to start with the garment, not the fabric. Ask yourself: what is this piece for, and in which season will it be worn most?
For summer leggings, fitted tees, bike shorts, or bodysuits, reach for cotton lycra. For autumn and winter hoodies, joggers, casual sets, and lounge wear, French terry is the more comfortable and appropriate choice. If you are sewing a full kids' capsule wardrobe, you will likely want both fabrics in your stash, one for warm-weather layers and one for cooler-season staples.
If you are just starting out with knit fabrics, it is also worth reading up on how knit fabrics differ from wovens more broadly. The post on jersey vs woven fabric is a useful starting point before you dive into the finer distinctions between individual knit types.
Both cotton lycra and French terry reward careful fabric selection and thoughtful construction. Once you have sewn a few garments in each, you will develop a feel for which one suits a given project instinctively. Until then, when in doubt, let the garment's function guide your choice.