You can knit a beanie on straight needles by working flat, then seaming the sides together

A beanie knitted on straight needles is worked as a flat rectangle that you fold and sew closed at the end. This is different from circular needles, which let you knit in the round without seaming. Straight needles are easier to manage if you are new to knitting, and the seam actually sits invisibly at the back of the hat once you finish it properly. The whole project takes about 6 to 10 hours of actual knitting time, depending on your speed and yarn weight.

The basic approach is: cast on stitches for the width of the hat, knit rows until the piece is long enough to wrap around your head, bind off, then sew the short ends together. You will also pick up stitches around the top opening to close it with a drawstring or ribbed edge. This guide walks you through each step so you end up with a hat that fits and looks finished.

Key Takeaways

  • Cast on 60 to 80 stitches depending on your head size and yarn weight, then knit in stockinette stitch (knit on the front, purl on the back) until the piece measures 18 to 22 inches long.
  • Sew the two short ends together using a mattress stitch, which hides the seam inside the hat and creates a professional finish.
  • Pick up stitches around the top opening and knit a ribbed cuff or drawstring to close the crown and prevent unraveling.
  • Block your finished beanie by pinning it to shape on a towel and letting it dry, which evens out the stitches and helps it hold its form.
  • Common mistakes include casting on too few stitches (making the hat too tight), knitting too loosely (creating a floppy hat), or skipping the mattress stitch seam (leaving a visible ridge).

Measure your head and choose your yarn weight

Measure around your head just above your ears where the beanie will sit. Most adult heads measure 20 to 23 inches around. Write this number down—you will use it to decide how many stitches to cast on. If you are knitting for a child, measure 16 to 19 inches; for a very large head, go up to 24 inches.

Yarn weight matters because it changes how many stitches you need. Worsted weight yarn (medium thickness) is the easiest to work with for a first beanie. Bulky yarn knits faster but creates a looser fabric that may not hold its shape as well. Fingering weight (thin yarn) takes longer but creates a denser, warmer hat. Buy yarn labeled worsted weight or #4 if you are starting out. You will need about 400 to 600 yards depending on how long you want the beanie to be.

Cast on the right number of stitches

The number of stitches you cast on determines the width of your hat. A general rule: multiply your head measurement by your gauge. Gauge is how many stitches fit in one inch when you knit with your chosen yarn and needles. Most worsted weight patterns use a gauge of 4 to 5 stitches per inch.

If your head measures 22 inches and your gauge is 4 stitches per inch, cast on 88 stitches (22 × 4). If your gauge is 5 stitches per inch, cast on 110 stitches (22 × 5). To find your gauge, knit a small test swatch (about 6 inches square) in stockinette stitch, measure how many stitches fit in one inch, then do the math. This step prevents a hat that is too tight or too loose.

Use the long-tail cast-on method, which creates a stretchy edge that feels comfortable against your forehead. Cast on your stitches loosely—if you pull too tight, the edge will be stiff and hard to work into later.

Knit the body in stockinette stitch until it reaches the right length

Stockinette stitch is the most common stitch for beanies. It looks like smooth V-shapes on the front and bumps on the back. To knit stockinette stitch on straight needles, knit every stitch on the front-facing rows, then purl every stitch on the back-facing rows. Alternate these rows for the entire body of the hat.

Knit until your piece measures 18 to 22 inches long, depending on how deep you want the beanie to sit. A shallower hat (18 inches) sits higher on the head and shows more forehead. A deeper hat (22 inches) pulls down lower and covers the ears more. Measure from the cast-on edge straight up the side of your work. Count your rows as you go—most beanies take 70 to 90 rows in worsted weight yarn.

Watch for tension as you knit. If your stitches are too tight, the hat will be stiff and hard to pull on. If they are too loose, the hat will sag and lose its shape. Aim for stitches that slide smoothly on the needle but hold their shape when you stop knitting. If you notice your tension changing halfway through, that is normal—just try to keep the later rows consistent with each other.

Bind off and seam the sides together with mattress stitch

Bind off all stitches loosely using the standard bind-off method: knit two stitches, pass the first stitch over the second, knit one more stitch, pass the previous stitch over it, and repeat until one stitch remains. Cut the yarn and pull it through the last stitch. Do not bind off too tightly or the top edge will pucker.

Now you have a flat rectangle. Fold it in half lengthwise so the two short ends meet. You will sew these ends together using mattress stitch, which creates an invisible seam. Thread a yarn needle with a length of yarn about 24 inches long. Starting at the bottom corner, insert the needle under the horizontal bar between the first and second stitch on one side, then under the corresponding bar on the other side. Move up one row and repeat, pulling gently every few stitches to close the gap. The seam will disappear inside the hat as you work. Sew all the way to the top, then weave in the loose end.

If mattress stitch feels confusing at first, watch a video demonstration—seeing the needle movement makes it much clearer than reading about it. The key is going under the bars (the horizontal threads between stitches) rather than through the stitches themselves.

Pick up stitches around the top and close the crown

Once the seam is closed, you have an open circle at the top of the hat. You need to pick up stitches around this opening and knit a cuff to close it. Turn the hat inside out so you can see the cast-on edge clearly. Using your straight needles, pick up one stitch in each cast-on stitch around the entire opening. You should pick up roughly the same number of stitches you originally cast on (around 88 to 110, depending on your size).

Knit in ribbed stitch (alternating knit and purl stitches) for 1 to 2 inches. Ribbed stitch looks like vertical lines and stretches more than stockinette, which makes it comfortable around the crown. For example, knit one stitch, purl one stitch, knit one stitch, purl one stitch, all the way across. Repeat this pattern for every row. After 1 to 2 inches of ribbing, bind off all stitches loosely.

If you prefer a drawstring instead of a ribbed cuff, knit only 4 to 6 rows of ribbing, then bind off. Thread a separate cord or I-cord through the stitches to cinch the top closed. This gives you a more adjustable fit.

Block the beanie to even out the stitches and set the shape

Blocking is the step that makes a handmade beanie look polished. Fill a sink or basin with cool water and add a small amount of wool wash (or gentle shampoo if you do not have wool wash). Submerge the beanie and let it soak for 10 to 15 minutes. Gently squeeze the soapy water through the yarn without wringing or twisting. Rinse in cool water until the water runs clear.

Squeeze out excess water by rolling the beanie gently in a clean towel. Lay it flat on a dry towel and shape it into a circle, smoothing out any lumps or wrinkles. Pin it to the towel if needed to hold the shape. Let it dry completely, which usually takes 24 to 48 hours depending on humidity. Once dry, the stitches will look even, the edges will lie flat, and the hat will hold its shape much better.

Frequently Asked Questions

What if my beanie is too tight or too loose after I seam it?

If it is too tight, you cast on too many stitches or your gauge was tighter than expected. Rip out the seam, pick up stitches along one edge, and knit a few extra rows to add width before reseaming. If it is too loose, the opposite happened—you cast on too few stitches. Rip and reknit with more stitches, or accept the looser fit and wear it pulled down lower on your head.

Can I use a different stitch pattern instead of stockinette?

Yes. Garter stitch (knitting every row) creates a thicker, bouncier hat. Seed stitch (alternating knit and purl in a checkerboard pattern) looks textured. Any stitch works as long as you knit enough rows to reach your target length. Just remember that different stitches have different gauges, so test your gauge before casting on.

What is the mattress stitch and why not just use a regular seam?

Mattress stitch uses the horizontal bars between stitches to create a seam that lies flat and invisible. A regular seam (sewing through the stitches themselves) creates a visible ridge that looks lumpy. Mattress stitch takes a few minutes longer but makes the finished hat look professional.

How do I know when to stop knitting the body?

Measure from the cast-on edge straight up the side of your work. Stop when it reaches 18 to 22 inches, depending on how deep you want the beanie. If you are unsure, knit to 20 inches—that is a safe middle ground for most head sizes and hat styles.

Do I have to block the beanie?

Blocking is not required, but it makes a big difference in how the finished hat looks and feels. Unblocked beanies can look bumpy and feel stiff. Blocked beanies look smooth and professional. If you are short on time, at least wet the beanie, squeeze out water, shape it, and let it air dry—that is a quick version of blocking that still helps.