Corset Calculator

Light (10%)creates gentle shaping — the corset smooths your silhouette without aggressive cinching. This is a great starting point for first-time corset wearers or for corsets intended for all-day comfort.

Moderate (15%)is the most common reduction for everyday corsets. You’ll see a noticeable waist definition that works well under clothing. Most ready-to-wear corset patterns are drafted at this level.

Firm (20%)produces a dramatic hourglass shape. At this level, the corset requires proper seasoning (breaking in gradually over 1–2 weeks) before wearing at full tightness. Fabric and bone quality matter significantly here.

Tight (25%)is the maximum reduction recommended for custom corsets. This level is for experienced corset wearers with seasoned corsets made from coutil or heavy twill drill with steel boning. Never jump straight to 25% — work up to it.

Rib springis the difference between your underbust measurement and your corseted waist. A spring of 2–4 inches is typical. If it’s too small, the corset may slide upward; too large, and the top edge may gap.

Hip springis the difference between your hip measurement and your corseted waist. Larger hip springs (6–8 inches or more) require careful panel shaping — extra flare in the lower panels or gussets to accommodate the curve from waist to hip.

Both values are calculated automatically from your measurements and reduction level. If your springs seem extreme, consider adjusting the reduction level or consulting a corset fitting reference.

Steel spiral bonesare flexible in all directions, making them ideal for curved seam lines. They follow the body’s contours and are the primary choice for most corset panels.

Flat steel bones are rigid and only bend in one direction. Use them alongside the back lacing (two on each side of the grommets) and at the centre front if you have a busk. They prevent the corset from folding or collapsing under tension.

Synthetic / plastic bonesare lightweight and flexible but do not provide enough support for a true corset. They’re fine for fashion corset tops or costumes, but not for waist reduction.

Bones should be cut 1 inch shorter than the panel height to allow clearance at the top and bottom edges. Always cap the ends with bone tips to prevent them from poking through the fabric.

Corset eyelets (grommets) are spaced approximately 1 inch apart on each side of the back opening. Use two-part grommets with washers — not single-piece snaps — for durability. Set them at least ½ inch from the fabric edge to prevent tearing.

The lacing gapis the space between the two back edges when the corset is laced. A gap of 1–3 inches is normal and expected. If the gap closes completely, the corset is too large; if it exceeds 3 inches, the corset is too small.

Use a strong, flat lacing cord (paracord or dedicated corset lacing). Start lacing from the top and bottom, meeting at the waist with “bunny ears” — two loops you can pull to adjust tightness. This distributes tension evenly.