How to Crochet a Phone Case for iPhone 18 Pro Max

US crochet terms throughout. Sizes here are worked out from gauge rather than from a finished sample, so swatch and measure as you go, and the pictures of finished pieces are illustrations. Made one? Send a photo through the contact page.

A crochet phone sleeve fails in one predictable way: it is chained to the phone’s width, seamed, and then the phone will not go in. The fabric does not only cover the front and back. It also wraps both edges, so the flat sleeve has to be wider than the phone. This page works out by how much, using one specific phone, and then makes the sleeve.

The iPhone 18 Pro Max body is 3.07 inches wide (78.0 mm), 6.43 inches tall (163.4 mm), and 0.34 inch thick (8.75 mm), per Apple’s tech specs. Those are the bare phone. No sleeve for this page was crocheted or fitted on a phone, and the pictures are illustrations. The method works for any phone. Put your own three numbers into the table.

US terms. US single crochet is UK double crochet. Abbreviations.

Five illustrated crochet phone sleeves in different colors — Illustration. Five colorways of the same rectangle. Not a sleeve measured on a phone.

How the sleeve is built

One rectangle of single crochet. The foundation chain sets the width. The rows build the length. Fold it in half so the fold is the bottom, seam the two sides, and leave the top open. There is no shaping and no separate base.

Looking down into a sleeve with a phone inside. The fabric runs around the phone's 3.07 inch face and its 0.34 inch edges, with a seam at each side. Notes: fabric all the way round is 2 times 3.41, which is 6.82 inches, so each flat face is 3.41 inches before seams, about 3.9 inches with seams and ease, 16 single crochet at 4 per inch rather than 13. — The sleeve has to cover the phone's edges as well as its face. That is the 0.34 inch most first sleeves forget.

Wrap a strip of paper around the phone the short way and mark where it meets. That length, about 6.82 inches here, is what the sleeve has to go around. A flat sleeve has two faces, so each face must be at least half: 3.41 inches. The side seams then take up roughly one stitch of the width, and you want a little ease so the phone slides. That makes the fabric about 3.9 inches wide.

The same thing happens at the bottom. The fold wraps the bottom edge, so each face starts about half the depth, 0.17 inch, above the fold. The pocket needs about 6.6 inches of depth on each side before the phone is covered.

Yarn and hook

An iPhone 18 Pro Max beside a tape measure, yarn, and a hook — Illustration. Measure against the phone you own, not a smaller one.

Smooth worsted cotton. Cotton slides on the phone’s glass and frame. Fuzzy yarn grips it, sheds lint into the ports, and pills inside. Yarn weight chart.
A hook that makes dense fabric, often US G/6 (4.0 mm). Drop a size if you can see light through the stitches. Hook chart.
The phone, without its case. If you keep a case on, measure the phone in its case instead.
Yarn needle, scissors.

Crochet a swatch at least 4 inches wide and measure stitches and rows per inch. A gauge swatch is worth it here, because the width has almost no room for error.

The worked example

Part	Arithmetic	Result
Around the phone	2 × (3.07 + 0.34)	6.82 in
One flat face	6.82 ÷ 2	3.41 in
Fabric width	3.41 + about 0.25 seams + about 0.25 ease	about 3.9 in
Stitches	3.9 × 4, rounded up	16 sc, chain 17
Pocket depth per side	6.43 + 0.17 at the fold + about 0.4 collar	about 7.0 in
Rows	2 × 7.0 × 5	70 rows

A chain of just over 3.07 inches is about 13 stitches at 4 stitches per inch. Seamed, that leaves roughly 3.0 inches inside a sleeve that needs 3.41.

Stage 1: chain and first row

Chain 17. Single crochet in the second chain from the hook and in each chain across. Ch 1, turn. (16)

A foundation chain of 17. The chain nearest the hook is skipped and the first sc goes into the 2nd chain from the hook, so row 1 has 16 sc. Checkpoint: the first row lying flat measures about 3.9 in. — Step 1. The chain next to the hook is skipped and does not count, so 17 chains give 16 sc.

Keep the chain looser than the rows, or use a hook one size larger for the chain only. A tight chain pulls the bottom edge in, and the fold will pucker.

Checkpoint: lay the first row flat. It should measure about 3.9 inches. Fold a strip of paper of that width around the phone. It should close with a little overlap.

Stage 2: the rectangle

Single crochet in each stitch across. Ch 1, turn. The ch 1 does not count as a stitch. (16)

Two rows of single crochet. Correct: the turning ch 1 sits beside the edge and the first sc of the new row goes into the first stitch, the last one made on the row below, so the count stays the same. Mistake: the first sc goes into the ch 1, outside the edge, which adds a stitch and makes the edge flare. — Where the first stitch of each row goes. Working into the ch 1 is the usual reason a 16-stitch sleeve grows to 17.

Count the stitches every 10 rows. Single crochet edges often gain a stitch when the first stitch goes into the turning chain, and each gained stitch is a quarter inch of looseness at that row.

Stop at about 70 rows, or when the rectangle folded in half covers the phone with a little collar above the top edge. Measure it lying flat, not hanging.

Rows 2 to 70: 16 sc every row. Rows of 16 sc drawn one symbol per stitch and worked back and forth, each starting with a turning chain (ch 1, not a st). Row 36 is highlighted. Every row: 16 sc. Count every 10 rows. Row 35 is the middle. With 70 rows, the fold lands between rows 35 and 36. — Step 2. The same 16 stitches on every row. The two halves of the sleeve meet at the middle row.

Checkpoint: fold the rectangle with the phone inside, without seaming. The two long edges should meet beside the phone with no strain. If they gap, the sleeve is too narrow. Start again with more stitches. Do not stretch it.

Stage 3: fold and seam

Fold the rectangle in half with the right side inside. Whipstitch each side from the fold to the top, through the outer loop of each edge stitch only. Going deeper into the stitch takes width from the inside. Turn it right side out so the seams are inside.

Drawn to scale. A flat piece 16 sc, 3.9 in wide and 70 rows, 14 in tall, folded at the dashed line into a pocket. Right side in. Whipstitch each side from the fold up, through the outer loops only. Top stays open. Each side ends up about 7 in deep: the phone's 6.43 in plus the fold and a collar. — Step 3. Drawn to scale: a 3.9 by 14 inch strip folds into a 3.9 by 7 inch pocket.

Slide the phone in before you weave the tails. It should go in without force and stay put when you tip the sleeve. If the opening fights you, the last rows are tighter than the rest. Redo them more loosely. Weave ends on the inside, where they cannot catch on the buttons. See weaving in ends.

Two edges laid side by side, right sides together. Correct: the needle passes through the outer loop of each edge stitch only, so the seam is flat and takes almost no width. Mistake: the needle goes through the whole stitch on both sides, which builds a thick ridge and takes width from the inside. — A seam through the outer loops keeps the inside width the sleeve was sized for.

Color

Joining terracotta yarn on the last loop of a cream stitch — Illustration. Change color on the last yarn-over so the new row starts clean.

Solid. Best first sleeve. You can see every stitch you need to count.

Two-tone. Work 35 rows in color A, change color, and finish in color B. The color change lands on the fold.

Stripes. Change every 4 rows. On a piece this small, two-row stripes read as noise. Cut the old color unless it returns within two rows. A strand carried up the side is on the inside of the seam, where it snags on the phone.

Keep every color the same yarn weight. A thinner yarn makes a narrower stripe, and the phone sticks there.

Make the optional flap a complete separate stage

For a straight eight-stitch flap, mark the middle eight stitches of the back rim and join at the first marked stitch. Row 1: ch 1, sc in each marked stitch (8). Rows 2–6: ch 1, turn, sc across (8). With the phone inside for marking, check it reaches the intended button location; add full rows if needed. Final row: ch 1, turn, sc 3, ch 3, skip 2, sc 3 (six sc and a loop). Test your button through the loop, remove the phone, then sew the button through the front wall alone. This replaces the unspecified optional shaping.

Troubleshooting

The phone will not go in. The sleeve was sized to the face, not around the phone. Recheck the width against 2 × (width + depth) ÷ 2, plus seams.

It goes in but sticks at the top. The camera plateau. Add a few loose rows to the collar, or work the last 4 rows with a larger hook.

The phone slides out when tipped. Too much ease, or a loose fabric. Redo with one fewer stitch or a smaller hook.

One side is longer than the other. Gained or lost stitches. Count back to the row where you still had 16.

The bottom corners stick out. The fold is not square. Refold along a single row.

Frequently asked

Does this work for a different phone?

Yes. Measure width, height, and depth, or look them up on the maker’s spec page, and redo the table.

Should I cut a hole for the camera?

No. The plateau sits at the top, and the open collar clears it. A hole in a single-crochet sleeve stretches and runs.

Does the sleeve protect the phone from a drop?

No. It keeps scratches and lint off the glass. It does not cushion a fall.

Can I sell sleeves I make?

A plain sleeve sized from published measurements is yours to make. Do not copy someone else’s charted motif onto it.

The same “fabric goes around, not across” rule sizes every folded sleeve in the device case guide, from a book to a laptop. A round tube sized for a smaller object is the pouch method on that same page.