A hemline is the folded edge at the bottom of a garment, and you sew it by folding the fabric up, pressing it flat, and stitching it down so the fold stays in place

The basic process is the same whether you use a sewing machine or hand-sew: you measure how much fabric to fold up, fold and press it, pin it so it does not shift, then stitch along the fold line. A machine hem is faster and stronger for everyday wear. A hand-sewn hem is invisible from the outside and works better on delicate fabrics or curved edges like armholes. Most people start with a machine hem on a straight edge like pants or a skirt, then move to hand-sewing once they understand the fold-and-stitch principle.

The hardest part is not the sewing—it is getting the fold straight and even. If your fold is crooked, your hem will look crooked no matter how neat your stitches are. That is why pressing and pinning matter more than speed.

Key Takeaways

  • Measure the finished length you want, then fold the fabric up twice (a double fold) to hide the raw edge and make the hem stronger.
  • Press the fold flat with an iron before you pin or sew, so the fabric stays in place and your stitches go in a straight line.
  • A machine hem on a straight edge takes 10 to 15 minutes; a hand-sewn hem on the same edge takes 30 to 45 minutes but is invisible from the outside.
  • The most common mistake is folding uneven amounts of fabric, which makes the hemline wavy—measure twice and pin every inch to prevent this.

Measure the finished length before you cut or fold anything

Put on the garment and have someone measure from the floor (or your desired finished length) up to where you want the hem to sit. Mark that spot with a pin or tailor's chalk. Take off the garment and measure from that mark down to the raw edge of the fabric. That distance is your hem allowance—the amount of fabric you will fold up.

For most garments, a hem allowance of 1.5 to 2 inches is standard. Pants and skirts usually take 1.5 to 2 inches. Dresses and lighter fabrics can go as low as 1 inch. If you are shortening something that was already hemmed, you may have less fabric to work with, so measure what you actually have before you plan.

Write down the measurement so you do not forget it while you are working. Measure at least three points around the garment (front, back, and sides) to make sure the finished length will be even all the way around.

Fold the fabric up twice and press it flat with an iron

Fold the raw edge of the fabric up by half your hem allowance. If your hem allowance is 2 inches, fold up 1 inch. Press this fold flat with a hot iron (check the garment label for the right temperature). This first fold hides the raw edge.

Now fold the fabric up again by the same amount—another 1 inch in this example. Press this second fold flat. You now have a double fold hem, which is the standard for most garments. The raw edge is completely hidden inside the fold, and the hem is twice as thick, which makes it stronger and less likely to fray.

Let the fabric cool for a minute after pressing. The crease will set better if you give it time. If you skip the iron and try to sew a fold that is not pressed, the fabric will shift under the needle and your hem will come out wavy.

Pin the fold every inch so it does not shift while you sew

Place pins perpendicular to the fold line (pointing toward the body of the garment, not along the edge). Space them about 1 inch apart all the way around. The pins hold the fold in place so it does not creep up or down while you are sewing.

Check that the fold is even as you pin. Measure from the fold line to the raw edge at a few points to make sure you folded the same amount everywhere. If one section is thicker than another, unfold that part, press it again, and re-pin.

Do not pin too close to the edge where you will sew. If you pin right on the stitch line, the needle will hit the pin and break. Pin about 0.25 inches below where your stitches will go.

Machine hem: stitch 0.125 inches from the fold using a straight stitch

Set your machine to a straight stitch and thread it with thread that matches the garment. Place the garment under the presser foot so the fold line runs along the 0.125-inch mark on the needle plate (most machines have this line marked). This distance is called the stitch distance or seam allowance—it is how far from the fold your stitches will be.

Sew slowly and remove pins as you approach them. Do not sew over a pin; stop, remove it, and continue. Sew all the way around the garment, keeping the fold line even with the 0.125-inch mark the whole time. When you reach the starting point, overlap your stitches by about 0.5 inches and backstitch to lock the thread.

Trim any loose threads and try on the garment. The hem should lie flat and the stitches should be hidden inside the fold when you look at the outside of the garment.

Hand hem: use a ladder stitch for an invisible seam on the inside

Thread a needle with thread that matches the garment and knot the end. Bring the needle up through the fold (not through the outer layer of fabric) about 0.25 inches from where you want to start. This hides the knot inside the fold.

Bring the needle out of the fold and take a tiny stitch (about 0.125 inches) straight across into the body of the garment, just above the fold line. Go back into the fold directly across from where you came out, and slide the needle along inside the fold for about 0.25 inches. Come back out and repeat. This stitch pattern—going back and forth between the fold and the garment—is called a ladder stitch or blind stitch. When you pull the thread gently, the fold closes and the stitches disappear inside.

Work your way around the garment, keeping your stitches small and even. When you reach the end, bring the needle out, wrap the thread around the needle twice, and push the needle back through the fold to lock it. Trim the thread.

Press the finished hem and check for puckers or loose spots

Once you have finished sewing, press the hem again with an iron to flatten it and set the stitches. Use a pressing cloth (a thin cotton cloth or even a clean kitchen towel) between the iron and the garment to avoid shine marks.

Try on the garment and look at the hem from all angles. It should be even all the way around, with no waves or puckers. If you see a wavy section, that usually means the fold was not pressed flat before sewing. You can sometimes fix this by pressing that section again and re-sewing if the stitches are loose.

Check that the stitches are find by gently pulling on the hem. If it feels loose or if you can see gaps between stitches, you may need to re-sew that section. A properly sewn hem should feel solid and not shift when you tug it.

Frequently Asked Questions

What if the hem is too short or too long after I sew it?

If it is too short, you can let out the hem by removing the stitches with a seam ripper (a small tool with a curved blade), unfolding the fabric, and re-measuring. If it is too long, you will need to cut off the excess fabric above the fold, then re-fold and re-sew. Always measure carefully before you sew to avoid this.

Can I use a sewing machine on stretchy fabric like knit or jersey?

Yes, but use a ballpoint needle (designed for knits) and a stretch stitch instead of a straight stitch. A regular needle and straight stitch can break the fibers in stretchy fabric. Hand-sewing with a ladder stitch also works well on knits because it has more give.

What thread color should I use?

Match the thread to the garment color as closely as you can. If the color is between two thread shades, choose the darker one—it is less visible. For a machine hem, the thread on the bottom of the garment (the bobbin thread) is what shows, so make sure that matches too.

How do I hem a curved edge like an armhole or neckline?

Curved edges are easier to hand-sew than machine-sew because you can follow the curve without the fabric bunching. Use a hand ladder stitch and take smaller stitches on the tightest curves. You can also use bias tape (a pre-folded strip of fabric) to bind a curve instead of folding the fabric itself.

Do I need to finish the raw edge before I fold and sew?

Not if you are using a double fold hem—the raw edge is hidden inside the fold and will not fray. If you are using a single fold (which is rare), you should finish the raw edge with a zigzag stitch or pinking shears to prevent fraying.