Make a splash in your cozy time with the Mermaid Tail Blanket, a magical crochet project that wraps you in warmth and whimsy! 🧜♀️🧶 With its flowing fin, textured stitches, and snug cocoon shape, this blanket transforms lounging into a fairytale escape. Whether you’re curled up with a book, binge-watching your favorite series, or just daydreaming of undersea adventures, this blanket brings a touch of enchantment to every moment.
Perfect for crocheters who love playful designs and comfy creations, this pattern invites endless customization. Choose ocean-inspired hues, add sparkly yarn for a shimmering tail, or size it up for a dreamy sleepover accessory. Whether you’re crafting for a little mermaid or indulging your own inner sea siren, the Mermaid Tail Blanket is a fin-tastic way to stitch up comfort—one magical loop at a time! 🌊🧵

🧜 Mermaid Tail Blanket Crochet Pattern
Transform your cozy evenings into magical underwater adventures with this crochet mermaid tail blanket! Featuring a ribbed ombré body and a wide ribbed fin, it’s as enchanting as it is snuggly. This pattern is designed to be photo-accurate to the beautiful blanket shown — with smooth vertical ribbing, a gentle gradient, and a wide flowing fin.
✨ Skill Level
Intermediate
This pattern uses:
- Front-post ribbing
- Working in the round
- Long, consistent stitch sections
- Gradual shaping
- Panel assembly
📏 Finished Size
Adult Size (as written):
- Total length: 150–155 cm / 59–61 in
- Width at hips (flat): 55–60 cm / 21.5–23.5 in
- Fin width (tip to tip): 70–75 cm / 27.5–29.5 in
Adjusting size:
Shorten or lengthen the body section, or reduce starting stitches for smaller sizes.
🧶 Yarn & Amounts
Yarn weight: Worsted / Aran (Category 4)
Choose a smooth yarn with good stitch definition.
Yarn Quantities (Adult)
- Light Aqua: ~600 g / ~1,200 m (1,310 yd)
- Medium Teal: ~500 g / ~1,000 m (1,090 yd)
- Deep Ocean Blue: ~400 g / ~800 m (875 yd)
Total: ~1,500 g / ~3,000 m (3,280 yd)
🪝 Tools & Notions
- 5.0 mm crochet hook (H/8)
- Yarn needle
- Scissors
- Stitch markers
🔡 Abbreviations (US Terms)
- ch – chain
- sl st – slip stitch
- dc – double crochet
- fpdc – front post double crochet
- bpdc – back post double crochet
- dc2tog – double crochet 2 together
- st(s) – stitch(es)
- rep – repeat
- FO – fasten off
🧵 Construction Overview
- Ribbed waistband
- Vertically ribbed body tube
- Gentle taper toward fin
- Two ribbed fin panels (lengthwise ribs)
- Fin assembly and attachment
🩱 Waistband
Worked in the round for stretch and comfort.
Foundation:
Ch 120, join with sl st (do not twist).
Rounds 1–6
fpdc, bpdc around (120 sts)
Do not turn.
🧜 Body Tube (Vertical Ribbing)
The ribbing runs vertically, creating a scale-like texture.
Body Rounds
Ch 2 (does not count as a stitch).
fpdc around, sl st to join.
Repeat continuously.
🎨 Color Transitions
Change colors smoothly using the last stitch of the previous round.
- Rounds 1–28: Light Aqua
- Rounds 29–52: Medium Teal
- Rounds 53 onward: Deep Ocean Blue
📐 Body Length
Continue fpdc rounds until body measures 115–120 cm / 45–47 in from waistband.
🔻 Tapering Toward the Fin
The taper is subtle and smooth.
Decrease Rounds
- Round 1: (18 fpdc, dc2tog) rep (114 sts)
- Rounds 2–5: fpdc around
- Round 6: (16 fpdc, dc2tog) rep (108 sts)
- Rounds 7–10: fpdc around
- Round 11: (14 fpdc, dc2tog) rep (102 sts)
- Rounds 12–15: fpdc around
Continue until total length reaches 145–150 cm / 57–59 in.
Transition Rounds
Work 2 rounds fpdc with no decreases to soften the fin join.
FO.
🐟 Tail Fin (Make 2 Panels)
The fin ribs run from base to tip, not side-to-side.
Foundation
Ch 78 (fin length).
Rows 1–6
Dc in 3rd ch from hook and across.
Ch 2, turn.
Rows 7–12
fpdc across, turn.
Widening Phase
Every 2 rows, add 1 dc at each end.
Continue until fin width reaches 70–75 cm / 27–29.5 in.
Tip Shaping
Work last 4 rows with no increases to elongate the fin tip.
FO.
Repeat for second panel.
🧵 Fin Assembly
- Place fin panels wrong sides together, ribs aligned.
- Whipstitch or sc evenly around edges.
- Do not pull tight—allow the fin to fan naturally.
- Align fin center with the back center of the body.
- Attach evenly across the opening.
Reinforce the center seam.
✨ Finishing
- Weave in all ends securely.
- Lightly steam or wet-block the fin only.
- Do not stretch the body section.
🌊 Final Notes
- The deep front-post ribbing creates the textured, scale-like surface.
- The fin is intentionally oversized for dramatic drape.
- No lining, stuffing, or drawstring is required.
Slip into your mermaid tail blanket, curl up on the sofa, and enjoy a cozy, flowing design that feels luxurious from waist to fin. 🧜♀️💙
