Paint Calculator

The Paint Calculator is an advanced online tool that accurately computes how much paint you need for wall painting and renovation projects. It provides two convenient input modes: direct area entry for simplicity, and room dimension entry (width, depth, ceiling height) with automatic wall area calculation.

For more precise estimates, you can configure advanced settings that account for actual painting scope. The tool allows you to deduct standard door and window areas, specify whether you plan to paint the ceiling, customize coverage per liter, adjust the number of coats, and set waste rate (default 5%). These features enable you to create a material purchasing plan that minimizes waste.

The calculation results display not only the base paint needed but also the recommended purchase quantity including waste margin. For common Japanese can sizes (0.7L, 1.6L, 4L, 7L, 14L), the tool automatically calculates the number of cans required, suggesting the most efficient purchase pattern. A detailed breakdown section shows the composition of wall area, ceiling area, and deductions, ensuring transparency in your estimates.