How to Cast On: The Long-Tail Method, Step by Step

Casting on puts the first row of loops on your needle; every row you knit grows from these. The long-tail cast-on is a versatile method that suits most projects: it is firm enough to hold its shape, stretchy enough for most edges, and tidy to look at. It is held the same way whether you knit in English or continental style.

It can look complicated the first time, because both hands are busy at once. In fact it is one movement, repeated. Follow the steps slowly, and after a few repetitions your hands will begin to remember the sequence.

What you need

• One knitting needle. You cast on onto a single needle; the second one waits until you start knitting.
• Your yarn. A smooth, light-colored, medium-weight yarn is the easiest to learn with.
• Scissors.

Two words will come up in every step:

• The tail: the free end of the yarn, which you measure before you begin.
• The working yarn: the strand that comes from the ball.

How long should the tail be?

The tail is used up as you cast on, so it must be long enough for every stitch, with a little left over to weave in at the end. There are two reliable ways to measure it.

The wrap method

1. Hold the end of the yarn against the needle with your thumb.
2. Wrap the yarn loosely around the needle, once for each stitch you need.
3. Add about 6 inches (15 cm) beyond the last wrap, to weave in later.
4. Pinch the yarn at that point and unwind the wraps.

The point you are pinching is where you will make your slip knot. Each wrap uses roughly as much yarn as one cast-on stitch on that needle, which is why this method is so dependable. Keep the wraps loose but not slack, just like the stitches themselves.

The rule of thumb

For medium-weight yarn, allow about 1 inch (2.5 cm) of tail per stitch, plus about 6 inches (15 cm) extra. Twenty stitches, for example, need a tail of about 26 inches (65 cm). Thicker yarn and larger needles use more yarn per stitch; thinner yarn uses less.

When you need a lot of stitches

For a long cast-on, measure with a test. Cast on 10 stitches, then pull them out and measure how much tail they used. Multiply that length by the number of tens you need, and add your extra length for weaving in.

How to make a slip knot

The slip knot is an adjustable loop that anchors the yarn to the needle. In the long-tail cast-on, it counts as your first stitch.

1. At the point you measured, cross the working yarn over the tail to form a loop.
2. Reach through the loop and pull a small fold of the working yarn through it, making a new loop.
3. Slip this new loop onto your needle.
4. Pull both strands gently to tighten the knot around the needle.

The slip knot should sit snugly on the needle but still slide along it. If it is tight enough to squeeze the needle, loosen it a little before you continue.

How to hold the yarn in the slingshot position

1. Hold the needle in your right hand with the slip knot on it, and rest your right index finger on the knot so it does not spin around the needle.
2. Let both strands hang down from the needle, with the tail toward you and the working yarn away from you.
3. Slide your left thumb and index finger between the two strands from below, so the tail lies over your thumb and the working yarn over your index finger.
4. Close your other three fingers around both strands, holding them lightly against your palm.
5. Turn your left palm upward and spread your thumb and index finger apart, like a slingshot.
6. Lower the needle a little, so the yarn forms a V from the needle to your thumb and finger.

You now have a loop of yarn around your thumb and a strand running from your index finger to the needle. Keep this position for the whole cast-on.

How to make each cast-on stitch

1. Bring the needle tip up through the loop around your thumb, passing under the strand nearest you.
2. Swing the tip over the top of the strand that runs from your index finger to the needle, and catch it.
3. Bring the tip back down through the thumb loop, carrying the caught strand with it.
4. Let the loop slide off your thumb.
5. Place your thumb back under the tail and spread your thumb and finger gently, to snug the new stitch onto the needle.

That is one stitch. Repeat steps 1 to 5 for each new stitch, returning to the slingshot shape every time. A short way to remember the movement: up through the thumb, over the finger, back down through the thumb.

How tight should cast-on stitches be?

Each new stitch should sit snugly around the needle without squeezing it:

• The stitches should slide along the needle easily.
• They should sit side by side, touching but not crammed together.
• Tighten each one by spreading your thumb and finger, not by yanking the tail.

If you struggle to push the stitches along the needle, they are too tight. If they hang in loose loops, tighten each one a little more as you go. What matters most is that they are all about the same size.

How to count your cast-on stitches

1. Hold the needle so the stitches face you.
2. Count the loops sitting on top of the needle, including the slip knot. The ridge of yarn running along the bottom is the base of the stitches, not extra stitches.
3. Count in groups of ten, touching each loop with a fingertip.
4. For a long cast-on, slip a stitch marker onto the needle after every 20 stitches as you go, so you never have to recount more than one group.
5. Count a second time before you start knitting.

When the count is right, move the needle to your left hand, pick up the empty needle in your right hand, and begin the first row with the working yarn. Our knit stitch tutorial picks up from exactly this point.

Common long-tail cast-on mistakes and how to fix them

The tail ran out before you finished

Without enough tail, you cannot complete the cast-on. Slide the stitches off the needle, unravel them and start again with a longer tail. Before you unravel, count how many stitches the tail made: that tells you how much yarn each stitch uses with your yarn and needle, so your next measurement can be exact.

The edge is too tight

Signs: the first row is a struggle to knit, the edge is narrower than the knitting above it, or it puckers and refuses to stretch.

How to fix it:

• Cast on over two needles held together, side by side, then carefully slide one of them out before you knit the first row.
• Or cast on with a needle one or two sizes larger than your project needle, then knit the first row with your usual needle.
• As you cast on, leave each stitch at its natural size rather than pushing the stitches tightly together on the needle.

The strands were swapped

The tail belongs over your thumb and the working yarn over your index finger. If you put the work down and pick it up again, it is easy to reverse them without noticing. The stitches still form, but the edge shows a small irregularity at the point where the strands changed places. Check before you resume. If you spot a change in the edge, unravel back to that point and continue with the strands in their proper places.

The stitches are uneven

If some stitches are loose and others tight, you are probably tightening each one differently. Try to make the same small spreading movement with your thumb and finger after every stitch. Slight differences matter less than they look while the stitches are on the needle.

When another cast-on is a better choice

The long-tail cast-on suits most first projects, but it is not the only one, and some situations call for something different:

• For very stretchy edges, such as the cuff of a top-down sock or a neckline that must stretch over the head, knitters often choose a stretchier variation such as the German twisted cast-on, or a tubular cast-on for ribbing.
• To add stitches partway through a piece, for example over a buttonhole, you need a cast-on that works from the working yarn alone, without a tail, such as the cable cast-on or the backward-loop cast-on.
• When a pattern names a specific cast-on, follow it: the designer chose it for that edge.

What to learn next

With your stitches on the needle, the next step is the knit stitch. For the whole path from first stitch to finished piece, see how to knit for beginners, and when you reach the end of your first piece, learn how to bind off.