What fullness ratio do tab top curtains need?

Tab top curtains use a lower fullness ratio of 1.5x. Because the tabs are fixed at intervals, too much fullness creates awkward bunching. The fabric hangs in soft folds between tabs.

How wide and spaced should tabs be?

Standard tab width is 4-6cm finished. Tab spacing (gap between tabs) is typically 10-20cm. Closer spacing gives a neater look; wider spacing creates deeper folds. The tab width plus spacing determines the drape pattern.

How long should curtain tabs be?

Tab length needs to loop over the pole. Measure the pole circumference (diameter x 3.14) and add 3-4cm for attaching to the curtain. A standard 28mm pole needs tabs about 13cm long.

Can I add buttons to tab tops?

Yes, buttoned tab tops allow easy removal for washing. Make the tab loop with one end folded under and a buttonhole, the other end with a button. This also adds a decorative detail.

SewCalcs

Tab Top Calculator — Tab Dimensions & Fabric

Calculate tab dimensions and fabric for tab-top curtains.

Pole Width

Finished Curtain Drop

Below the pole

Tab Width (finished)

Tab Spacing

Pole Circumference

Diameter x 3.14

Fabric Width

Fabric Price (optional)

How We Calculate This

Tab top curtains have fabric loops that slide onto the pole. The number of tabs is calculated from the curtain width and spacing.

The formula

Total width = Pole width × 1.5

Number of tabs = ceil(Total width ÷ (Tab width + Spacing)) + 1

Tab loop = Pole circumference + 4cm

Tab cut: Width × 2 + 3cm, Length = Loop + 4cm

Frequently Asked Questions

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Last updated: February 2026

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