Striped Diagonal Baby Blanket Tutorial – FREE Knitting Pattern for Beginners
There is something quietly magical about knitting a baby blanket. It is one of those projects that feels meaningful from the very first cast-on, and by the time you bind off, you have made something that might be wrapped around a little one for years. If you have been looking for a beginner-friendly pattern that looks far more impressive than the skill it requires, you have found it. This striped diagonal baby blanket is exactly that kind of project — simple in construction, beautiful in result, and completely free.
In this tutorial, I am going to walk you through every single step, from the yarn and needles you will need all the way to weaving in your last end. Whether you are brand new to knitting or returning after a long break, this pattern was designed with you in mind. The diagonal construction is achieved through a simple increase and decrease technique that creates that elegant bias direction without any complicated shaping. Add stripes, and you have a finished blanket that looks like it came from a boutique.
Let’s get into it.
Why a Diagonal Baby Blanket
Most beginner knitters start with rectangles worked flat, which usually means knitting back and forth in rows across a consistent number of stitches. A diagonal blanket works the same way — flat, back and forth — but it starts at a corner, grows outward with increases, and then tapers back in with decreases. The result is a square or rectangular blanket oriented on the bias, meaning the lines of stitches run diagonally rather than horizontally.
This diagonal direction has a few advantages. It creates a natural stretch along the diagonal, which makes the blanket drape beautifully. It also means that any striping you add will appear as diagonal stripes rather than horizontal rows, giving the finished piece a dynamic, intentional look. Many people see a diagonal striped baby blanket and assume it must have been difficult to make. The truth is the opposite — the technique is very approachable, and once you understand the rhythm of it, your hands will practically do it on their own.
There is also something practical about knitting diagonally. You can make the blanket any size you want simply by knitting more or fewer increase rows before you begin the decrease section. That kind of flexibility is wonderful when you are a new knitter still getting comfortable with the craft.
Materials You Will Need
Getting your materials together before you sit down to knit is always a good idea. Here is what this pattern calls for.
Yarn: You will need two colors of yarn for the stripes. A worsted weight yarn works beautifully for this project — it knits up quickly, is easy to handle, and produces a blanket with good body and warmth. Plan on approximately 400 to 500 yards per color for a standard baby blanket size of about 30 by 30 inches. Acrylic yarns are a practical choice for baby items since they are machine washable and hold up well to repeated laundering. If you want something with a natural fiber content, look for a superwash wool or a cotton blend.
Needles: US size 7 (4.5mm) or US size 8 (5mm) straight or circular needles. Either works for flat knitting. Many knitters prefer circular needles even for flat projects because the cord holds the stitches when the piece gets larger and heavier.
Notions: A pair of scissors, a yarn needle for weaving in ends, and stitch markers if you would like to use them (though they are not required for this pattern).
Gauge: Approximately 18 stitches and 24 rows to 4 inches in stockinette stitch on US size 7 needles, or 16 stitches and 22 rows on US size 8 needles. Gauge is less critical for a blanket than for a garment, but a significant deviation will affect the finished size. If you want a precise measurement, knit a quick swatch and adjust your needle size accordingly.
Abbreviations Used in This Pattern
Knitting patterns rely on shorthand, so let me define everything you will encounter here so there are no surprises mid-project.
CO — Cast on. The process of placing your initial stitches on the needle to begin knitting.
K — Knit. The basic knit stitch.
KFB — Knit front and back. A common increase stitch where you knit into the front loop of a stitch and then, without removing it from the left needle, knit into the back loop of the same stitch. This creates two stitches from one.
K2tog — Knit two together. A common decrease stitch where you insert your right needle through two stitches at once and knit them as if they were one. This reduces your stitch count by one.
YO — Yarn over. Wrapping the yarn around the needle to create a new stitch and a small eyelet hole. This pattern uses yarn over as a decorative increase along one edge.
BO — Bind off. The process of securing your stitches at the end of a project so they cannot unravel.
RS — Right side. The side of your work that faces outward in the finished item.
WS — Wrong side. The side that faces inward.
Pattern Notes
This blanket is worked entirely in garter stitch, which means you knit every stitch on every row. There is no purling in this pattern. Garter stitch is wonderfully beginner-friendly because you never have to think about which row you are on in terms of stitch technique — every row is the same. It also produces a fabric that lies flat without curling, which is exactly what you want for a blanket.
The increases happen at the beginning of every row during the first half of the blanket, creating the triangle that grows outward from the starting corner. Once your blanket has reached the desired width, you begin the decrease section, which mirrors the increase section and brings the blanket back down to a single point at the opposite corner.
Stripes are added by simply switching colors at the beginning of a new row. Because you are always adding your new color on the same edge, the ends can be managed neatly along one side of the blanket.
Casting On and Getting Started
Begin by casting on 3 stitches in your main color. Any cast-on method works here, but the long-tail cast-on gives a neat, stretchy edge if you are comfortable with it. The cable cast-on and the backward loop cast-on are also perfectly fine options.
With your 3 cast-on stitches ready, you are going to work the setup rows before beginning the stripe sequence.
Row 1 (RS): Knit all 3 stitches.
Row 2 (WS): KFB, knit to end. You now have 4 stitches.
Row 3: KFB, knit to end. You now have 5 stitches.
Row 4: KFB, knit to end. You now have 6 stitches.
Continue in this fashion — knitting into the front and back of the first stitch on every row — until your blanket has reached the desired width. For a 30-inch blanket, you will want to continue increasing until your needle holds approximately 130 to 140 stitches, depending on your gauge. This is a good time to lay your work flat and measure the width to confirm you are on track.
Introducing the Stripe Sequence
Now comes the fun part. You are going to add your second color to create those beautiful diagonal stripes. The stripe sequence in this pattern uses 8 rows of each color, which creates bold, even stripes. You can absolutely adjust this — 4 rows per color creates a thinner stripe, while 12 rows creates a wider one. Experiment to find what you love.
To join your second color, simply drop the working yarn at the beginning of a new row and pick up the new color. Leave a 6-inch tail to weave in later. Do not cut the first color — let it hang at the edge. In garter stitch, you will be able to carry the unused color loosely up the side of the blanket for several rows before picking it back up, which reduces the number of ends you need to weave in.
Stripe sequence:
Work 8 rows in Color A (your main color), then 8 rows in Color B (your contrast color). Repeat this sequence throughout the entire blanket — both the increase section and the decrease section.
Because you are working in garter stitch and always starting new rows from the same edge, the stripes will look clean and even on both sides of the blanket. This is one of the quiet advantages of garter stitch — it is fully reversible, so your blanket will look polished from either direction.
Completing the Increase Section
Continue working the increase sequence — KFB at the beginning of every row — while maintaining the stripe sequence. You do not need to make any changes to accommodate the stripes. Just keep increasing and switching colors every 8 rows as described.
As your blanket grows, you will see those gorgeous diagonal stripes developing across the fabric. The stitches themselves run on the diagonal because of the increase structure, and the stripe changes add horizontal movement across that diagonal canvas. It is a very satisfying combination to watch develop.
When your blanket has reached your target width — again, approximately 130 to 140 stitches for a 30-inch blanket — you are ready to begin the decrease section. Make a note of your stitch count so you can track your progress through the decrease rows.
Working the Decrease Section
The decrease section is the mirror image of the increase section. Instead of adding a stitch at the beginning of every row, you will now remove one. The decrease used here is K2tog, worked at the beginning of each row.
Continue your stripe sequence exactly as before. Nothing changes about the color pattern — you simply replace the KFB at the start of each row with a K2tog.
Decrease row: K2tog, knit to end.
Work this decrease row every row, alternating colors every 8 rows, until you are back down to 3 stitches on your needle.
As your stitch count drops, you will see the blanket coming to a point at the opposite corner from where you began. The finished shape will be a square oriented like a diamond, which you can display with one of the flat sides at the top — giving you a perfectly traditional square blanket — or rotated 45 degrees for a more modern presentation.
Binding Off
When you have 3 stitches remaining, it is time to bind off. Work a standard bind-off as follows.
Knit 2 stitches. Insert the left needle into the first stitch you knitted (the one on the right needle farther from the tip). Lift it up and over the second stitch and off the needle. Knit 1 more stitch. Lift the first stitch over the new stitch and off the needle. You should have 1 stitch remaining. Cut your yarn, leaving a 6-inch tail, and pull the tail through the remaining loop to secure it.
Finishing Your Blanket
Finishing is the step that turns a piece of knitting into a finished object, and it is worth taking the time to do it well.
Weaving in ends: Thread each yarn tail onto your yarn needle and weave it through the stitches on the wrong side of the blanket. Work through several stitches in one direction, then double back in the other direction for security. Trim any excess yarn close to the fabric.
Blocking: Blocking is the process of wetting or steaming your finished knitting to set the stitches and even out the fabric. For a baby blanket, fill a basin with cool water and submerge the blanket completely. Allow it to soak for 15 to 20 minutes, then gently squeeze out the water — do not wring. Roll the blanket in a dry towel and press to remove more moisture. Lay it flat on a blocking mat or clean towel, shape it to your desired dimensions, and allow it to dry completely. Blocking makes a tremendous difference in the appearance of finished knitting and is especially helpful for garter stitch, which can look a little compressed straight off the needles.
Tips for Knitting This Blanket
A few pieces of advice that will make your experience smoother and more enjoyable.
Keep track of your rows. Even experienced knitters lose count. A simple row counter — physical or on your phone — is helpful for keeping track of where you are in the stripe sequence.
Carry your yarn up the side rather than cutting it at every color change. If you are switching colors every 8 rows, you can twist the unused yarn around the working yarn at the edge of every row to keep it from creating a long loose loop. After 8 rows, you simply pick it back up. This works well for stripe sequences up to about 12 rows.
Be consistent with your tension. Try to knit with the same tension throughout the project. If you know you knit tightly, go up a needle size. If you knit loosely, try a needle size down. Even tension produces an even fabric.
Do not be discouraged by the slow start. The first several inches of a corner-to-corner blanket grow slowly because your row widths are short. Once the blanket gets wider, it feels like it is flying. Stick with it through those early rows and you will find your rhythm.
Personalizing Your Blanket
One of the best things about a simple base pattern is how much room it gives you to make it your own. Here are a few ideas for customizing this blanket.
Choose colors that match the nursery. A blanket in soft sage green and cream feels different from one in bold navy and mustard, even though it is the same pattern. Color choice is one of the most powerful tools you have as a knitter.
Try different stripe widths. As mentioned earlier, 4, 6, 8, or 12 rows per stripe all produce different looks. You could even do an irregular stripe sequence — maybe 4 rows, then 8 rows, then 12 rows, then back down again — for something a little more unexpected.
Add a simple border. Once your blanket is complete, you can pick up stitches around the perimeter and knit a few rows of garter stitch as a border. This frames the blanket nicely and gives it a polished, finished appearance.
Use a self-striping or variegated yarn as one of your colors. Pairing a solid color with a self-striping yarn can create beautiful, complex-looking results without any extra effort on your part.
A Note on Yarn Substitution
The pattern is written with a standard worsted weight yarn in mind, but you can absolutely substitute. A DK weight yarn on smaller needles will produce a lighter, airier blanket. A bulky yarn on larger needles will produce something thicker and warmer that also knits up faster. If you substitute yarn, be sure to check that you are happy with your gauge and adjust your needle size as needed. The principles of the pattern — cast on 3, increase every row, decrease every row — stay the same regardless of yarn weight.
Sharing Your Finished Blanket
When you finish, I would love for you to share what you made. Whether you post it on Instagram, Pinterest, Ravelry, or anywhere else you hang out in the crafting community, tagging your work helps other knitters find patterns that work and encourages the whole community. If you make this blanket as a gift, take a photo before you hand it over — baby items have a way of disappearing quickly into new families who are rightfully too busy to document the lovely things they receive.
Knitting for babies is one of the most generous things you can do with your hands. The blanket you just made will probably outlast many things you could have bought, and someone is going to wrap a small, sleepy person in it and think of you. That is pretty wonderful.
Happy knitting.
