Elastic Length Calculator
Calculate exactly how much elastic to cut for waistbands, cuffs, lingerie, and swimwear.
Measure the body part where elastic will sit
Elastic Reduction Reference by Type & Application
| Elastic Type | Application | Snug Ratio | Standard Ratio | Relaxed Ratio |
|---|---|---|---|---|
| Non-roll / Woven | Waistband | 75% | 85% | 90% |
| Braided | Waistband | 72% | 83% | 88% |
| Knit / Plush-back | Waistband | 75% | 85% | 90% |
| Lingerie / Swimwear | Swimwear | 65% | 75% | 80% |
| Lingerie / Swimwear | Underwear | 70% | 78% | 85% |
| Fold-over (FOE) | Neckline | 80% | 88% | 93% |
| Any | Sleeve / Leg Cuff | 75% | 85% | 90% |
How to Use the Elastic Length Calculator
- Measure the body part where the elastic will sit (e.g., your natural waist for a waistband).
- Select the type of elastic you are using — different elastic types have different stretch and recovery properties.
- Select the application (waistband, cuff, underwear, etc.) and your desired fit.
- Click Calculate to get your cut elastic length.
Elastic Types
- Non-roll / Woven: Firm, holds shape well. Good for waistbands. Does not narrow when stretched.
- Braided: Narrows when stretched, loses strength when pierced by needles. Best used in a casing. Most economical type.
- Knit / Plush-back: Soft and comfortable against skin. Good for activewear and waistbands worn against the body.
- Lingerie / Swimwear: Narrow, strong, and often has a decorative edge. Designed for high-stretch, chlorine-resistant use.
- Fold-over (FOE): Used to finish edges while adding stretch. Common on necklines and armholes.
Tips
- Always cut elastic about 2–3" longer than calculated, then try on and trim to fit. It is easier to remove length than add it back.
- When joining elastic ends, overlap 1" and sew a box or zigzag stitch to secure. Factor this into your cut length.
- Elastic loses stretch and recovery over time — use quality elastic rated for the application (swimwear elastic for swimwear, etc.).