The Boxy Cat Jumper

A beginner drop-shoulder pullover for cats

Worsted weight · knitted flat · seamed

This is a cat-sized garment (not for humans or dogs). It is a boxy drop-shoulder pullover: the front and back are plain rectangles, the shoulders are seamed, and short sleeves are sewn to the straight armhole edges. A ribbed boatneck (no neck shaping) pulls on over the head. The cropped body ends in front of the hind legs.

Skill level: Beginner. You need to cast on, knit, purl, work 2x2 rib and stockinette, bind off, and sew seams.

Sizes

S (M, L, XL, 2XL)

Instructions are written for S, with M, L, XL, and 2XL in parentheses. When only one number is given, it applies to all sizes.

Choose a size by the cat’s chest, measured around the widest part of the ribcage, just behind the front legs. When in doubt, size up.

Finished measurements

Chest circumference: 14½ (16, 17½, 19¼, 22½)" / 37 (40.5, 44.5, 49, 57) cm
Back length (neck edge to hem): 10 (11½, 13, 14½, 16)" / 25.5 (29, 33, 37, 40.5) cm
Back/front width: 7¼ (8, 8¾, 9½, 11¼)" / 18.5 (20.5, 22, 24, 28.5) cm
Neck opening width (center, each piece): 5½ (6½, 6½, 7¼, 8)" / 14 (16.5, 16.5, 18.5, 20.5) cm
Shoulder seam (each side): ¾ (¾, 1¼, 1¼, 1½)" / 2 (2, 3, 3, 4) cm
Armhole depth: 3½ (4, 4½, 5, 5¾)" / 9 (10, 11.5, 12.5, 14.5) cm
Sleeve length: 2 (2¼, 2½, 3, 3½)" / 5 (5.5, 6.5, 7.5, 9) cm

Ease at chest is about 2" (5 cm).

Check length on your cat before you sew: from the base of the neck (where a collar would sit) to about 1½–2" (4–5 cm) in front of the hind legs. Add or subtract stockinette rows if needed.

Yarn

Worsted weight (CYC 4), washable — acrylic or superwash wool. Pet jumpers get dirty and will be washed.

Yardage: 130 (170, 210, 260, 340) yards / 119 (155, 192, 238, 311) m

Skeins (200 yd / 183 m per 100 g): 1 (1, 2, 2, 2)

Solid colors show the simple shape well. Avoid novelty/eyelash yarns — claws catch in them.

Needles

• US 7 / 4.5 mm straight (or circular used flat), for rib
• US 8 / 5 mm straight (or circular used flat), for stockinette
• or sizes needed to obtain gauge

Notions

• Tapestry needle
• Scissors
• Tape measure
• 4 stitch markers or scrap yarn (optional, to mark shoulder stitches)
• Pins or locking stitch markers for seaming

Do not add buttons, beads, bells, or other small notions a cat could chew off and swallow.

Gauge

20 stitches and 28 rows = 4" (10 cm) in stockinette stitch on larger needles, after blocking.

5 sts = 1" (2.5 cm). 7 rows = 1" (2.5 cm).

Swatch, wash, and dry the way you will wash the jumper. Change needle size if needed until you match this gauge. If your gauge is off, the jumper will not fit.

Notes

Construction. Back and front are identical rectangles. Sleeves are knitted flat from the top down and sewn to the straight armholes. All work is flat — no circular knitting.

Fit. The dropped shoulder seam sits on the upper front leg. The jumper should be easy to pull over the head, sit at the base of the neck, and end before the hind legs. It should not bind at the chest or under the legs.

Safety.

• Supervise the first wears. Remove the jumper if the cat panics, chews the fabric, or cannot walk, sit, or use the litter box normally.
• Do not leave a cat unattended in clothing until you know it is comfortable.
• Fabric that is too loose can catch on claws, teeth, or furniture; fabric that is too tight restricts movement. Aim for the ease given above.
• Stop using the jumper if stitches snag or holes appear.

Dressing. Scrunch the jumper, ease it over the head, then put one front paw through a sleeve and the other through the second sleeve. Smooth the back down. Reverse to remove.

Abbreviations (US)

BO — bind off
CO — cast on
k — knit
k2tog — knit 2 stitches together (1 stitch decreased)
p — purl
rep — repeat
RS — right side
St st — stockinette stitch (knit RS rows, purl WS rows)
st(s) — stitch(es)
WS — wrong side
2x2 rib — *k2, p2; rep from * to end, every row (works on a multiple of 4 sts when knitting flat)

Schematic (not to scale)

BACK / FRONT (identical)

  |  4 (4, 6, 6, 8) sts   28 (32, 32, 36, 40) sts   4 (4, 6, 6, 8) sts  |
  |  shoulder seam        boatneck (left open)      shoulder seam      |
  |<---------------------- 7¼ (8, 8¾, 9½, 11¼)" ---------------------->|
  |                         36 (40, 44, 48, 56) sts                     |
  |                                                                    |
  |                         length 10 (11½, 13, 14½, 16)"              |
  |                                                                    |
  |                         1" rib at hem                              |
  |____________________________________________________________________|


SLEEVE (make 2)

  CO edge = armhole edge, 36 (40, 44, 48, 56) sts
  |<------ 7¼ (8, 8¾, 9½, 11¼)" circumference ------>|
  |                                                  |  length
  |               decrease 1 row                     |  2 (2¼, 2½, 3, 3½)"
  |              2x2 rib cuff                        |
  |<---- 24 (28, 28, 32, 36) sts -------------------->|

Back

With smaller needles, CO 36 (40, 44, 48, 56) sts.

Hem rib Work 2x2 rib (*k2, p2; rep from * to end) until the piece measures 1" (2.5 cm) from the CO edge, ending with a WS row.

Body Change to larger needles. Work in St st (knit RS, purl WS) until the piece measures 9 (10½, 12, 13½, 15)" / 23 (26.5, 30.5, 34.5, 38) cm from the CO edge, ending with a WS row. (1" hem rib + this St st section = total length minus the 1" neck rib.)

Neck rib Change to smaller needles. Work 2x2 rib until the piece measures 10 (11½, 13, 14½, 16)" / 25.5 (29, 33, 37, 40.5) cm from the CO edge, ending with a WS row.

BO in rib pattern. Fasten off, leaving a 12" (30 cm) tail for seaming.

Stitch check: 36 (40, 44, 48, 56) sts throughout. Width = 36 (40, 44, 48, 56) ÷ 5 = 7.2 (8, 8.8, 9.6, 11.2)" ≈ 7¼ (8, 8¾, 9½, 11¼)". Two pieces = chest 14½ (16, 17½, 19¼, 22½)". ✓

Front

Work exactly as for the Back. Front and back are identical; the boatneck is created when you seam only the outer shoulder stitches.

Sleeves (make 2)

With larger needles, CO 36 (40, 44, 48, 56) sts.

Row 1 (WS): Purl.
Row 2 (RS): Knit.
Row 3 (WS): Purl.

Decrease row (RS):

• S: K6, [k2tog] 12 times, k6. 24 sts rem.
  (6 + 24 + 6 = 36 sts used; 6 + 12 + 6 = 24 rem ✓)
• M: K8, [k2tog] 12 times, k8. 28 sts rem.
  (8 + 24 + 8 = 40 sts used; 8 + 12 + 8 = 28 rem ✓)
• L: K6, [k2tog] 16 times, k6. 28 sts tem.
  (6 + 32 + 6 = 44 sts used; 6 + 16 + 6 = 28 rem ✓)
• XL: K8, [k2tog] 16 times, k8. 32 sts rem.
  (8 + 32 + 8 = 48 sts used; 8 + 16 + 8 = 32 rem ✓)
• 2XL: K8, [k2tog] 20 times, k8. 36 sts rem.
  (8 + 40 + 8 = 56 sts used; 8 + 20 + 8 = 36 rem ✓)

24 (28, 28, 32, 36) sts. All multiples of 4 for 2x2 rib. ✓

Change to smaller needles.

Next row (WS): *K2, p2; rep from * to end.

Continue in 2x2 rib until the sleeve measures 2 (2¼, 2½, 3, 3½)" / 5 (5.5, 6.5, 7.5, 9) cm from the CO edge, ending with a WS row.

BO in rib pattern. Fasten off, leaving a 16" (40 cm) tail for seaming.

Finishing

Weave in ends that will not be used for seaming. Block all four pieces to the finished measurements and let them dry fully.

1. Join shoulders

Lay front and back with RS together, neck-rib edges matching.

Using mattress stitch (or backstitch) and the long BO tail, sew the first 4 (4, 6, 6, 8) sts of the right shoulder together through the bound-off edge. Fasten off.

Repeat on the left shoulder: sew 4 (4, 6, 6, 8) sts.

The center 28 (32, 32, 36, 40) sts of each piece stay open — this is the boatneck.

Check: 4 + 28 + 4 = 36 (S) ✓
4 + 32 + 4 = 40 (M) ✓
6 + 32 + 6 = 44 (L) ✓
6 + 36 + 6 = 48 (XL) ✓
8 + 40 + 8 = 56 (2XL) ✓

Fit the neck now. Pull the neck opening over the cat’s head (or around a tape measure equal to the head).

• Too tight to go over the head: take out 1–2 sts of seaming on each shoulder.
• Slides off the neck: sew 1–2 extra sts on each shoulder.

2. Set in the sleeves

With RS together, match the CO edge of one sleeve to one armhole:

• Center of the sleeve CO edge sits at the shoulder seam.
• Each half of the sleeve CO runs down the side edge of the front and the back, for 3½ (4, 4½, 5, 5¾)" / 9 (10, 11.5, 12.5, 14.5) cm from the shoulder.

Pin. The sleeve CO (36, 40, 44, 48, 56 sts = 7¼, 8, 8¾, 9½, 11¼") matches the armhole (front depth + back depth = 7, 8, 9, 10, 11½"). Ease any extra in evenly. Sew with mattress stitch.

Repeat for the second sleeve.

3. Side and sleeve seams

With RS together, sew each underarm-to-hem side seam and each sleeve underarm seam. You can work this as one continuous seam from cuff BO, up the sleeve, through the underarm, and down to the hem.

Side seam length (hem up to underarm): 6½ (7½, 8½, 9½, 10¼)" / 16.5 (19, 21.5, 24, 26) cm
(Body length 10 (11½, 13, 14½, 16) − armhole 3½ (4, 4½, 5, 5¾) = 6½ (7½, 8½, 9½, 10¼) ✓)

4. Ends and a final check

Weave in remaining ends on the WS. If the boatneck edge rolls, a light steam on the rib (acrylic: hold the iron above the fabric, do not press) will settle it.

Put the jumper on the cat. Confirm:

• It goes on over the head without a struggle.
• Front legs move freely in the sleeves.
• The hem sits in front of the hind legs.
• The cat can walk, sit, and lie down.

If the body is long, open the side seams, shorten from the hem, re-rib if you cut, and reseam. If it is short, you would need to reknit the body — measuring first avoids this.

Care

Wash as the yarn label directs. Superwash wool and most acrylics: gentle machine or hand wash, cool water, lay flat to dry. Check seams after washing. Discard the jumper if it is holey, stretched out of shape, or the cat has started to eat it.

That’s the whole jumper — two rectangles, two short sleeves, four seams.