Zipper Length Helper
Find the right zipper length and type for any garment or project.
Measure the seam opening the zipper will close
Standard Zipper Lengths for Common Garments
| Garment / Project | Typical Opening | Recommended Zipper | Zipper Type |
|---|---|---|---|
| Dress (back) | 18–22" | 20–22" | Invisible or dress |
| Skirt (back or side) | 7–9" | 9" | Invisible or dress |
| Pants fly | 6–8" | 7–9" | Trouser/jeans |
| Jeans fly | 5–7" | 7" | Jeans/metal teeth |
| Pillow (18") | 12–14" | 14" | All-purpose or invisible |
| Tote bag | 10–14" | 12–14" | All-purpose |
| Jacket / Hoodie | 20–28" | Measure + 1" | Separating |
| Cosmetic bag | 7–10" | 9–10" | All-purpose or nylon coil |
Zipper Type Guide
| Type | When to Use | Notes |
|---|---|---|
| Invisible / Concealed | Dresses, skirts, blouses — hidden seam look | Requires an invisible zipper foot. Opens to one side of seam. |
| All-purpose / Dress | General garments, home dec, pillows | Most common type. Comes in many colors and lengths. |
| Separating | Jackets, hoodies, cardigans, vests | Splits fully apart at bottom. Must match garment length exactly. |
| Trouser / Jeans | Pants, jeans, shorts with fly front | Short, sturdy. Metal or nylon teeth. 7" or 9" common. |
| Exposed / Decorative | Fashion garments, bags, sportswear | Zipper and tape are visible as a design element. |
| Waterproof | Outdoor gear, rain jackets, swim bags | Sealed teeth. Do not sew through tape — use clips or special feet. |
How to Use the Zipper Length Helper
- Measure the seam opening where the zipper will be inserted — from the top stop point to the bottom stop point.
- Select your project type from the dropdown.
- Click Find Zipper Length to see the recommended standard zipper size plus the next size up and down.
Key Rule: Always Round Up
- Zippers come in standard lengths. Always buy the next size up from your opening length — you can shorten a zipper, but you cannot lengthen one.
- For invisible zippers: buy at least 1" longer than your opening.
- For separating zippers on jackets: measure the exact finished garment front opening and match it precisely.
Shortening a Zipper
- To shorten a zipper, sew a new bar tack (hand or machine) at the desired length, then trim the excess tape below the new stop.
- For all-purpose zippers: cut from the bottom. For separating zippers: only shorten from the top.