Crochet Vibrant Rainbow Ripple Afghan Free Pattern

Introduction

This vibrant rainbow ripple afghan is the perfect project for anyone who has mastered the basic double crochet and wants to make something truly eye-catching. The alternating peaks and valleys create a stunning, flowing visual effect that brightens up any room it lands in. Worked in worsted weight yarn with a simple two-row repeat, it grows quickly and feels soft and cozy in the lap as you go. Whether you are a confident beginner or a seasoned crocheter, this colorful masterpiece is a joy to stitch from the first red row to the final violet one.

Materials Needed

• Yarn: Worsted weight (category 4) acrylic or acrylic-blend yarn in seven rainbow colors — red, orange, yellow, green, blue, indigo, and violet — approximately 200 yards of each color (about 1,400 yards total).
• Hook: Size H/8 (5 mm) crochet hook.
• Notions: Scissors and a tapestry needle for weaving in ends.
• Finished size: Approximately 48 inches wide by 14 inches tall (each ripple is about 4 inches wide and 4 rows measure 1 inch).

Abbreviations

• ch: chain — a loop made by pulling yarn through a loop on the hook.
• dc: double crochet — a tall stitch worked with one yarn over before inserting the hook.
• dc2tog: double crochet 2 together — a decrease that turns two stitches into one.
• sc: single crochet — a short, dense stitch used here for the border.
• st(s): stitch(es).

Gauge

4 dc = 1 inch, 4 rows = 1 inch in the ripple pattern, and each ripple measures approximately 4 inches wide. To check, work a small swatch of the ripple pattern and measure a 4-inch section; adjust your hook size if needed to match.

Tips Before You Start

• Count your chain carefully. The foundation chain must be a multiple of 14 plus 3 (171 chains). Recount in groups of 14 before you begin Row 1 so the ripples line up perfectly.
• Keep your peaks and valleys consistent. The pattern always decreases twice, then increases with 2 dc, 3 dc, 2 dc. Watch that the 3-dc group sits at the top of each peak.
• Change colors at the end of a row. Finish the last stitch of Row 8 with the new color to keep the color changes neat, and switch every 8 rows following the rainbow sequence.
• Don't stress the edges. The turning chain and final stitches are easy to miss; count the 168 stitches at the end of each row until you find your rhythm.

Step-by-Step Instructions

Foundation Row

Foundation: Ch 171 (multiple of 14 + 3).

Row 1

Row 1: Dc in 4th ch from hook (counts as first dc), dc in next 2 ch, *(dc2tog over next 2 ch) twice, dc in next 2 ch, 2 dc in next ch, 3 dc in next ch, 2 dc in next ch, dc in next 2 ch; repeat from * across, ending with dc in last 3 ch (168 sts).

Row 2

Row 2: Ch 3 (counts as dc), turn. Dc in first dc, dc in next 2 dc, *(dc2tog over next 2 dc) twice, dc in next 2 dc, 2 dc in next dc, 3 dc in next dc, 2 dc in next dc, dc in next 2 dc; repeat from * across, ending with dc in last 2 dc, dc in top of turning ch (168 sts).

Rows 3–56 (Ripple Pattern and Color Changes)

Rows 3–8: Repeat Row 2 (168 sts). At the end of Row 8, change to orange.

Rows 9–16: Repeat Row 2 (168 sts). At the end of Row 16, change to yellow.

Rows 17–24: Repeat Row 2 (168 sts). At the end of Row 24, change to green.

Rows 25–32: Repeat Row 2 (168 sts). At the end of Row 32, change to blue.

Rows 33–40: Repeat Row 2 (168 sts). At the end of Row 40, change to indigo.

Rows 41–48: Repeat Row 2 (168 sts). At the end of Row 48, change to violet.

Rows 49–56: Repeat Row 2 (168 sts). Fasten off after Row 56.

Border

Rnd 1: With violet, join yarn with a slip stitch in any corner. Ch 1, sc evenly around the entire blanket, working 1 sc in each dc along the top and bottom edges and 1 sc in each row end along the sides, with 3 sc in each corner. Join with a slip stitch to the first sc. Fasten off.

Assembly and Finishing

This afghan is worked in one piece, so no seaming is required. Weave in all yarn ends using the tapestry needle, threading each tail back and forth through the back of several stitches to secure it. Block lightly by misting with water and pinning to the finished measurements (about 48 by 14 inches), or gently steam the edges to help the ripples lie flat. Allow to dry completely before using or gifting.

Pro Tips and Variations

• Make it larger: Add multiples of 14 chains to the foundation to widen the blanket, or repeat the 8-row color blocks to lengthen it.
• Try a different palette: Swap the rainbow for a single color with a contrasting border, or use a self-striping yarn for automatic color changes.
• Add a thicker border: Work a second round of sc in a contrasting color for a crisp, finished frame that makes the ripples pop.