Printable Seam Allowance Conversion Charts
Print-ready reference guides for accurate sewing measurements
📊What These Charts Do
These printable conversion charts provide instant reference for converting between imperial and metric seam allowance measurements. Perfect for your sewing room wall, pattern storage, or project notebook.
🖨️How to Use These Charts
1. Click the print button on any chart you need
2. Print at 100% scale for accuracy
3. Laminate or mount on cardstock for durability
4. Keep handy while sewing for quick reference
Complete Conversion Reference
| Imperial | Metric (mm) | Metric (cm) | Decimal | Common Use |
|---|---|---|---|---|
| 1/8″ | 3mm | 0.3cm | 0.125 | French seam trimming |
| 3/16″ | 5mm | 0.5cm | 0.1875 | Very narrow allowances |
| 1/4″ | 6mm | 0.6cm | 0.25 | Quilting, lightweight fabrics |
| 5/16″ | 8mm | 0.8cm | 0.3125 | Narrow curves |
| 3/8″ | 10mm | 1.0cm | 0.375 | European standard |
| 7/16″ | 11mm | 1.1cm | 0.4375 | Between metric standards |
| 1/2″ | 13mm | 1.3cm | 0.5 | Medium weight fabrics |
| 9/16″ | 14mm | 1.4cm | 0.5625 | Intermediate measurement |
| 5/8″ | 15mm | 1.5cm | 0.625 | US commercial standard |
| 11/16″ | 17mm | 1.7cm | 0.6875 | Wide allowances |
| 3/4″ | 19mm | 1.9cm | 0.75 | Heavy fabrics |
| 7/8″ | 22mm | 2.2cm | 0.875 | Extra wide allowances |
| 1″ | 25mm | 2.5cm | 1.0 | Maximum standard width |
Quick Reference Guide
Quilting Standard
1/4″
6mm
Perfect for piecing quilt blocks and lightweight fabrics
European Standard
3/8″
1cm
Common in European patterns and metric countries
Medium Weight
1/2″
1.3cm
Good for cotton, linen, and medium fabrics
US Commercial
5/8″
1.5cm
Standard for American commercial patterns
Heavy Fabrics
3/4″
2cm
Best for denim, canvas, and upholstery fabrics
Maximum Width
1″
2.5cm
For alterations and very heavy materials
Fabric-Specific Recommendations
Choose the Right Seam Allowance for Your Fabric
Chiffon, Organza, Silk
1/4″ – 3/8″ (6-10mm)
Delicate fabrics need narrow allowances to prevent bulk
Cotton, Linen, Rayon
1/2″ – 5/8″ (1.3-1.5cm)
Medium weight fabrics work with standard allowances
Wool, Tweed, Coating
5/8″ – 3/4″ (1.5-2cm)
Heavy fabrics need wider allowances for stability
Denim, Canvas, Duck
5/8″ – 3/4″ (1.5-2cm)
Sturdy fabrics benefit from generous allowances
Jersey, Knits, Spandex
1/4″ – 1/2″ (6-13mm)
Stretch fabrics need narrow allowances to maintain elasticity
Lace, Eyelet, Mesh
1/4″ – 3/8″ (6-10mm)
Delicate materials require careful handling with narrow seams
Quilting Cotton
1/4″ (6mm)
Traditional quilting standard for accurate piecing
Upholstery, Tapestry
3/4″ – 1″ (2-2.5cm)
Very heavy fabrics need maximum allowances
Pattern Brand Standards
| Imperial | Metric (mm) | Metric (cm) | Decimal | Common Use |
|---|---|---|---|---|
| 1/8″ | 3mm | 0.3cm | 0.125 | French seam trimming |
| 3/16″ | 5mm | 0.5cm | 0.1875 | Very narrow allowances |
| 1/4″ | 6mm | 0.6cm | 0.25 | Quilting, lightweight fabrics |
| 5/16″ | 8mm | 0.8cm | 0.3125 | Narrow curves |
| 3/8″ | 10mm | 1.0cm | 0.375 | European standard |
| 7/16″ | 11mm | 1.1cm | 0.4375 | Between metric standards |
| 1/2″ | 13mm | 1.3cm | 0.5 | Medium weight fabrics |
| 9/16″ | 14mm | 1.4cm | 0.5625 | Intermediate measurement |
| 5/8″ | 15mm | 1.5cm | 0.625 | US commercial standard |
| 11/16″ | 17mm | 1.7cm | 0.6875 | Wide allowances |
| 3/4″ | 19mm | 1.9cm | 0.75 | Heavy fabrics |
| 7/8″ | 22mm | 2.2cm | 0.875 | Extra wide allowances |
| 1″ | 25mm | 2.5cm | 1.0 | Maximum standard width |
Quick Reference Guide
Quilting Standard
1/4″
6mm
Perfect for piecing quilt blocks and lightweight fabrics
European Standard
3/8″
1cm
Common in European patterns and metric countries
Medium Weight
1/2″
1.3cm
Good for cotton, linen, and medium fabrics
US Commercial
5/8″
1.5cm
Standard for American commercial patterns
Heavy Fabrics
3/4″
2cm
Best for denim, canvas, and upholstery fabrics
Maximum Width
1″
2.5cm
For alterations and very heavy materials
Fabric-Specific Recommendations
Choose the Right Seam Allowance for Your Fabric
Chiffon, Organza, Silk
1/4″ – 3/8″ (6-10mm)
Delicate fabrics need narrow allowances to prevent bulk
Cotton, Linen, Rayon
1/2″ – 5/8″ (1.3-1.5cm)
Medium weight fabrics work with standard allowances
Wool, Tweed, Coating
5/8″ – 3/4″ (1.5-2cm)
Heavy fabrics need wider allowances for stability
Denim, Canvas, Duck
5/8″ – 3/4″ (1.5-2cm)
Sturdy fabrics benefit from generous allowances
Jersey, Knits, Spandex
1/4″ – 1/2″ (6-13mm)
Stretch fabrics need narrow allowances to maintain elasticity
Lace, Eyelet, Mesh
1/4″ – 3/8″ (6-10mm)
Delicate materials require careful handling with narrow seams
Quilting Cotton
1/4″ (6mm)
Traditional quilting standard for accurate piecing
Upholstery, Tapestry
3/4″ – 1″ (2-2.5cm)
Very heavy fabrics need maximum allowances
Pattern Brand Standards
| Pattern Brand | Seam Allowance Included | Standard Width | Origin | Notes |
|---|---|---|---|---|
| Simplicity | ✅ Yes | 5/8″ (1.5cm) | USA | Most common US brand |
| Butterick | ✅ Yes | 5/8″ (1.5cm) | USA | Premium fitting focus |
| McCall’s | ✅ Yes | 5/8″ (1.5cm) | USA | Fashion-forward designs |
| Vogue | ✅ Yes | 5/8″ (1.5cm) | USA | Designer collaborations |
| Burda Style | ❌ No | Add 1.5cm | Germany | Must add your own allowances |
| New Look | ✅ Yes | 5/8″ (1.5cm) | UK | Budget-friendly patterns |
| Jalie | ✅ Yes | 1cm (3/8″) | Canada | Activewear specialist |
| Style Arc | ✅ Yes | 1cm (3/8″) | Australia | Modern silhouettes |
| Merchant & Mills | ✅ Yes | 1cm (3/8″) | UK | Modern British design |
| Japanese Patterns | ✅ Yes | 1cm (3/8″) | Japan | Precise fitting methods |
🖨️ Printing Instructions
- Scale: Always print at 100% – never use “Fit to Page”
- Paper: Use standard 8.5×11″ (A4) white paper
- Quality: Print in high quality mode for clear text
- Test: Verify measurements with a ruler after printing
- Durability: Laminate charts for long-term use
- Storage: Keep charts flat or in a binder for easy access