How far apart should press studs be?

For babywear: 3-5cm apart. For adult garments: 5-8cm. For home furnishings: 8-15cm. Closer spacing gives a more secure closure but uses more snaps.

What size snaps should I use?

Small (8-10mm) for lightweight fabrics and babywear. Medium (12-15mm) for shirts and dresses. Large (17-21mm) for jackets and outdoor wear. The snap should be strong enough to hold but easy to open.

What types of snaps are available?

Sew-on snaps are traditional and suit most fabrics. No-sew (prong) snaps punch through fabric with a tool. Magnetic snaps suit bags and purses. Kam snaps are popular for babywear and nappy covers.

How do I attach sew-on snaps?

Place the ball half on the overlap (right side) and the socket half on the underlap (wrong side). Sew through each hole 4-5 times with a hand needle. Keep stitches small on the right side of fabric.

SewCalcs

Snap Spacing Calculator — Even Snap Placement

Calculate even snap placement and quantities.

Closure Length

Number of Snaps

Top Offset

Bottom Offset

How We Calculate This

Snaps are evenly spaced between top and bottom offsets. The spacing is calculated by dividing the usable length by the number of gaps.

The formula

Usable length = Closure - Top offset - Bottom offset

Spacing = Usable length ÷ (Snaps - 1)

Frequently Asked Questions

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Last updated: February 2026

All calculations are estimates. Always verify quantities before cutting or purchasing fabric.