Calculadora de Cortinas (Tamanho)
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
Formula
largura_tecido = janela × franzido; altura_tecido = janela + bainha
About this calculator
This calculator helps determine the amount of fabric needed to make curtains. Simply enter the window width and height, the gather factor (recommended 2x for pleated curtains), and the hem allowance. The calculation considers the total fabric width (including seams if needed) and the height with added hem and heading.
How it works: the fabric width is obtained by multiplying the window width by the gather factor. If the result exceeds the standard fabric width (usually 1.40 m), the system calculates how many fabric panels are needed and the total width with seams. The fabric height is the window height plus the hem allowance (default 0.30 m). The final result is the total yardage in meters.
Use this calculator when planning curtains for living rooms, bedrooms, or kitchens. It's useful for both home sewers and those ordering fabric from stores. It avoids waste and ensures you buy the exact amount. Ideal for pleated, gathered, or straight curtains.
Cautions: the gather factor varies by style (1.5x for light gathering, 2x for medium, 3x for wide pleats). Check the actual width of your fabric (some fabrics are 1.50 m or 1.60 m). Remember to add extra margin for alignment and possible cutting errors. It is recommended to add 10% extra.
Frequently asked questions
What gather factor should I use?
For wide pleats use 3x; for medium gathering use 2x; for light gathering use 1.5x. The recommended default is 2x.
Do I need to include hem allowance?
Yes, the calculator already adds a default allowance of 30 cm (15 cm for hem and 15 cm for heading). You can adjust this value.
How do I calculate if my fabric has a different width than 1.40 m?
The calculator allows you to adjust the fabric width. Enter the actual width of your fabric (e.g., 1.50 m or 1.60 m) for an accurate calculation.
Should I buy extra fabric?
It is recommended to add 10% extra for possible cutting errors or alignment. The calculator does not include this margin automatically.