How to increase and decrease in amigurumi crochet

If you have ever stared at the words "inc" and "dec" in an amigurumi pattern and felt a small wave of panic, you are in good company. These two techniques are the engine behind every plump amigurumi belly, every pointy ear, and every perfectly round head. Once you understand what they actually do — add a stitch or remove a stitch — the shapes that seem like magic start to make complete sense.

What an increase actually does

One stitch in, two stitches out

An increase is simply two single crochets worked into the same stitch. In most amigurumi patterns you will see it written as "inc" or "2 sc in next st." When you place two stitches where one used to be, your stitch count grows by one per increase. Working a round where you increase in every stitch doubles your count — which is exactly how a flat magic ring grows into a circle, and how that circle eventually curves into a sphere.

The process is straightforward: insert your hook into the next stitch, yarn over, pull up a loop, yarn over, pull through both loops (that is your first sc). Without moving to the next stitch, insert your hook into the same stitch again and work a second sc. You have just increased.

Increases almost never cause problems because they are additive — you are always working into a stitch you can see. If you are struggling to count your stitches and rows after a round of increases, a stitch marker in the first stitch of each round is your best friend.

What a decrease actually does — and why "invisible" matters

One stitch fewer, with no visible gap

A standard single-crochet decrease (sc2tog) pulls through both loops of two consecutive stitches to merge them into one. It works, but it leaves a small horizontal bar on the fabric that shows through even when stuffed. The invisible decrease — also called the slip-stitch decrease — is the go-to method for amigurumi because it hides almost completely on the right side.

Here is how to work it: insert your hook through the front loop only of the next stitch, then through the front loop only of the stitch after that. You now have three loops on your hook. Yarn over and pull through the first two loops (the two front loops), then yarn over again and pull through the remaining two loops. Done — two stitches have become one, with almost no visible bump on the outside.

You will find invisible decreases written as "dec," "invdec," or "sc2tog (FLO)" depending on the pattern designer. If a pattern just says "dec," it is nearly always expecting the invisible method for amigurumi work. If you are curious about how this interacts with no-sew shaping techniques, the same principle applies — fewer seams means your shaping needs to be even more precise.

Reading the stitch counts in a pattern

Most amigurumi patterns list the running stitch count at the end of each round in parentheses, for example: Round 5: inc in each st around. (12) That "(12)" tells you exactly how many stitches you should have when the round is finished. If your count does not match, something happened in that round — not several rounds later. Stop, recount, and fix it before continuing.

A typical sphere starts with a magic ring, grows through several increase rounds, works a few even rounds, then closes with matching decrease rounds. For a 6-stitch start the sequence often looks like this:

• R1: 6 sc in magic ring (6)
• R2: inc in each st (12)
• R3: [sc, inc] × 6 (18)
• R4: [2 sc, inc] × 6 (24)
• R5–9: sc in each st (24)
• R10: [2 sc, dec] × 6 (18)
• R11: [sc, dec] × 6 (12)
• R12: dec × 6 (6)

Notice the decrease rounds are the mirror image of the increase rounds. This symmetry is what makes the shape close so neatly. If you want to understand the underlying technique of crocheting in the round, that foundation article covers spirals vs. joined rounds in detail.

Common shaping mistakes and how to fix them

Why your amigurumi looks lumpy — and how to smooth it out

The most common mistake beginners make is inserting the hook through both loops for a decrease instead of the front loops only. The result is a ridge on the outside of the piece. If you notice this after a few rounds, it is worth unraveling back and fixing it — the ridges become very visible once the piece is stuffed and the fabric is stretched tight.

Another frequent problem is accidentally skipping the increase. When you work two sc into one stitch, the first sc sits in the stitch and the second tends to slide toward the gap between stitches. If you are not watching closely, that second sc can slip into the next stitch instead. Use your thumb to hold both stitches in place after the first sc before inserting for the second.

Tension also matters enormously in decreases. If your yarn is pulled too tightly, the front loops of the target stitches will be hard to access. Slightly looser tension helps keep the fabric pliable. This is also worth keeping in mind if you are working on getting even tension overall — amigurumi benefits from slightly tighter tension than, say, a blanket, but not so tight you cannot get your hook through.

Shaping beyond spheres: tapered limbs and flat pieces

Once you are confident with increases and decreases in a round piece, the same logic applies to shaped limbs. A tapered arm might increase for a few rounds, stay even, then decrease to a tip. An ear might start with a small number of stitches, increase outward, and never close — leaving an open flat disc.

Flat amigurumi pieces (like a flower or a leaf) use increases along certain edges and not others to create asymmetry. If you have tried the guide on crocheting amigurumi ears, you have already worked with partial shaping — one side increases while the other stays even, resulting in a curved rather than circular edge.

Body shaping for characters follows the same principle at a larger scale. A pear-shaped body might increase rapidly through the lower rounds, plateau, then begin decreasing around the middle to create a waist. The animal body construction guide shows exactly how these sequences translate into recognizable animal forms.

Frequently asked questions