Baby crochet mermaid tail pattern (free + easy for beginners)

Q: Is this a free crochet baby mermaid tail pattern?

Yes. This baby crochet mermaid tail pattern is free to view on the blog and includes step-by-step instructions for two sizes and two length options.

Q: Can I make the mermaid tail waist-length or chest-length?

Yes. Instructions are included for both waist-length and chest-length versions for each size.

Q: Can I sell items made from this pattern?

Yes. You may sell finished items made from this pattern, but you may not redistribute or sell the pattern itself.

Want the cutest baby photo prop ever? This baby crochet mermaid tail pattern is an easy, cozy project that makes your little one look like a tiny mermaid. It includes two baby sizes (0–3 months and 3–6 months) and two length options (waist-length or chest-length), so you can choose the fit you like best. Scroll down for the free pattern, plus simple steps for adding the fin.

Quick answer: Baby crochet mermaid tail pattern
This free crochet pattern makes a baby mermaid tail in two sizes (0–3 months and 3–6 months). The tail is worked in the round from the bottom up, and you’ll add the fin last.

Lovable Loops free Baby Crochet Mermaid Tail Pattern

Why you’ll love this baby mermaid tail

Perfect for photo shoots
A fun baby shower gift
Cute for baby’s first Halloween
Includes two lengths (waist or chest)

Tip: Want a matching accessory? Pair it with your starfish appliqué for a sweet headband.

Baby crochet mermaid tail pattern details

This section covers the skill level, sizes, materials, gauge, and important notes you’ll need before starting the baby crochet mermaid tail pattern.

Skill level

Advanced beginner. This pattern uses simple stitches and shaping, plus a fin added at the end.

Materials needed

J-10 (6 mm) crochet hook: Use this size (or the hook size that helps you meet gauge).
Worsted weight yarn (#4): Soft and easy to care for.
Yarn needle: For weaving in ends.
Scissors: For cutting yarn.
Stitch markers (optional): Helpful for keeping track of rounds.

Printable PDF version

Prefer an ad-free, printable copy? You can get the PDF in my Etsy shop: Crochet Mermaid Tail Pattern.

Size chart

Size	Chest	Waist	Hips
0-3 Months	16 inches	18 inches	19 inches
3-6 Months	17 inches	19 inches	20 inches

Baby Mermaid Tail Size Chart

Gauge

12 stitches and 6 rounds = 4 inches

Crochet abbreviations

tr = treble crochet
sc = single crochet
dc = double crochet
ch/chs = chain/chains
st/sts = stitch/stitches
rnd/rnds = rounds/rounds

Pattern notes

Make the tail first, then add the fin.
Choose waist-length or chest-length.
The fin pattern is the same for both sizes.
Worked in the round from the bottom up.
The beginning chain does not count as a stitch.
Join each round with a sl st to the first stitch.
Repeat instructions between * across the round.
Written in US crochet terms.

Magic circle alternative

If you don’t like the magic circle: ch 5, make 12 tr in the 5th ch from the hook, join (12 sts).

Crochet baby mermaid tail pattern instructions

Follow the step-by-step crochet instructions below to make the baby mermaid tail in either waist-length or chest-length, with sizes for 0–3 months and 3–6 months.

0–3 month baby mermaid tail

Rnd 1: Magic circle, 12 tr, join (12)
Rnd 2: Ch 3, 2 tr in 3 sts, tr in 3 sts, join (18)
Rnd 3: Ch 3, 2 tr in 2 sts, tr in 7 sts, join (22)
Rnd 4: Ch 3, 2 tr in 2 sts, tr in 9 sts, join (26)
Rnd 5: Ch 3, 2 tr in 2 sts, tr in 11 sts, join (30)
Rnd 6: Ch 3, 2 tr in 2 sts, tr in 13 sts, join (34)
Rnd 7: Ch 3, 2 tr in 3 sts, tr in 14 sts, join (40)
Rnd 8: Ch 3, 2 tr in 3 sts, tr in 17 sts, join (46)
Rnd 9: Ch 3, 2 tr in 3 sts, tr in 20 sts, join (52)

Waist-length (0–3 months)
Rnds 10–20: Ch 3, tr in each st, join (52)
Rnd 21: Ch 1, sc in each st, join and fasten off

Chest-length (0–3 months)
Rnds 10–27: Ch 3, tr in each st, join (52)
Rnd 28: Ch 1, sc in each st, join and fasten off

3–6 month baby mermaid tail

Waist-length (3–6 months)
Rnds 11–23: Ch 3, tr in each st, join (58)
Rnd 24: Ch 1, sc in each st, join and fasten off

Chest-length (3–6 months)
Rnds 11–33: Ch 3, tr in each st, join (58)
Rnd 34: Ch 1, sc in each st, join and fasten off

Fin for the baby crochet mermaid tail pattern

Lay the mermaid tail flat with the increase section centered on the back of the tail. (figure 1)

Join yarn on the side of the tail between rounds 5 and 6. Chain 1 and single crochet in the same space. (figure 2)

Single crochet evenly around the bottom opening of the tail, working in the following order:

Down one side of the tail
Slip stitch in the center at the bottom
Up the opposite side

Continue until you reach the starting point between rounds 5 and 6. Do not fasten off. Begin the fin rows below. (figure 3)

Direction key:
→ = work away from the tail
← = work toward the tail

Fin rows:

← Row 1: Ch 36, dc in 2nd ch from hook and in each remaining ch, sl st in 2nd sc on tail (35 sts) (figure 4)

→ Row 2: Ch 2, dc in back loops only across (34 sts)
← Row 3: Sl st in first st, ch 2, dc in front loops only across, sl st in 3rd sc on tail (33 sts)
→ Row 4: Ch 2, dc in back loops only across (32 sts)
← Row 5: Sl st in first st, ch 2, dc in front loops only across, sl st in 4th sc on tail (31 sts)
→ Row 6: Ch 2, dc in back loops only across (30 sts)
← Row 7: Sl st in first st, ch 2, dc in front loops only across, sl st in 5th sc on tail (29 sts)
→ Row 8: Ch 2, dc in back loops only across (28 sts)
← Row 9: Sl st in first st, ch 2, dc in front loops only across, sl st in 6th sc on tail (27 sts)
→ Row 10: Ch 2, dc in back loops only across (26 sts)
← Row 11: Sl st in first st, ch 2, dc in front loops only across, sl st in 7th sc on tail (25 sts)
→ Row 12: Ch 2, dc in back loops only across (24 sts)
← Row 13: Sl st in first st, ch 2, dc in front loops only across, sl st in 8th sc on tail (23 sts)
→ Row 14: Ch 2, dc in back loops only across (22 sts)
← Row 15: Sl st in first st, ch 2, dc in front loops only across, sl st in 9th sc on tail (21 sts)
→ Row 16: Ch 2, dc in back loops only across (20 sts)
← Row 17: Sl st in first st, ch 2, dc in front loops only across, sl st in 10th sc on tail (19 sts)
→ Row 18: Ch 2, dc in back loops only across (18 sts)
← Row 19: Sl st in first st, ch 2, dc in front loops only across, sl st in 11th sc on tail (17 sts)
→ Row 20: Ch 2, dc in back loops only across, 2 dc in last st (18 sts)
← Row 21: Ch 2, 2 dc in first st, dc across, sl st in 12th sc on tail (19 sts)
→ Row 22: Ch 2, dc in back loops only across, 2 dc in last st (20 sts)
← Row 23: Ch 2, 2 dc in first st, dc across, sl st in 13th sc on tail (21 sts)
→ Row 24: Ch 2, dc in back loops only across, 2 dc in last st (22 sts)
← Row 25: Ch 2, 2 dc in first st, dc across, sl st in 14th sc on tail (23 sts)
→ Row 26: Ch 2, dc in back loops only across, 2 dc in last st (24 sts)
← Row 27: Ch 2, 2 dc in first st, dc across, sl st in 15th sc on tail (25 sts)
→ Row 28: Ch 2, dc in back loops only across, 2 dc in last st (26 sts)
← Row 29: Ch 2, 2 dc in first st, dc across, sl st in 16th sc on tail (27 sts)
→ Row 30: Ch 2, dc in back loops only across, 2 dc in last st (28 sts)
← Row 31: Ch 2, 2 dc in first st, dc across, sl st in 17th sc on tail (29 sts)
→ Row 32: Ch 2, dc in back loops only across, 2 dc in last st (30 sts)
← Row 33: Ch 2, 2 dc in first st, dc across, sl st in 18th sc on tail (31 sts)
→ Row 34: Ch 2, dc in back loops only across, 2 dc in last st (32 sts)
← Row 35: Ch 2, 2 dc in first st, dc across, sl st in 19th sc on tail (33 sts)
→ Row 36: Ch 2, dc in back loops only across, 2 dc in last st (34 sts)
← Row 37: Ch 2, 2 dc in first st, dc across, sl st in 20th sc on tail (35 sts)

Finishing

Fasten off and weave in all ends.

Crochet baby mermaid tail pattern FAQs

Is this a free crochet baby mermaid tail pattern?
Yes! This baby crochet mermaid tail pattern is free to view on my blog. It includes step-by-step instructions for two sizes and two length options.

What skill level is this crochet mermaid tail pattern?
This pattern is best for advanced beginners. You’ll use basic stitches, work in the round, and follow simple shaping instructions.

What sizes does this baby mermaid tail fit?
The pattern includes two baby sizes: 0–3 months and 3–6 months.

Can I make the mermaid tail waist-length or chest-length?
Yes! Instructions are included for both waist-length and chest-length versions for each size.

What yarn works best for this baby crochet mermaid tail?
Worsted weight (#4) yarn works best. Choose a soft, baby-friendly yarn that’s comfortable and washable.

Is this crochet mermaid tail safe for babies?
This pattern is intended for supervised use, such as photo shoots or dress-up. It should not be used for sleeping or unsupervised wear.

Can I adjust the size of the mermaid tail?
You can slightly adjust the fit by changing your hook size or adding length before finishing, but the pattern is written specifically for baby sizes.

Do I need to know how to use a magic circle?
A magic circle is used in the pattern, but an easy chain-based alternative is included if you prefer not to use one.

How is the mermaid fin attached?
The fin is crocheted directly onto the tail using rows of double crochet stitches worked back and forth.

Can I sell items made from this pattern?
Yes, you may sell finished items made from this pattern. Please do not redistribute or sell the pattern itself.

More crochet patterns for babies

Explore the gallery below to find more free crochet baby hat patterns and your next quick, giftable project.

Crochet baby hat patterns

Scroll the gallery below to explore more free crochet baby hat patterns and find your next quick, giftable project.

Crochet baby blanket patterns

Discover more free crochet baby blanket patterns in the gallery below and get inspired for your next cozy baby project.

Let’s connect!

I’d love to see what you’re making! Share your finished project and follow along for more free crochet patterns and tutorials.

📌 Don’t forget to pin this pattern for later!
Happy crocheting! 🧶
— Melissa