The standard sizes for architectural plans and engineering plans are different, so it will depend on what type of drawing you’re looking at. Architectural drawing sizes are based on the ARCH scale, while engineering drawing paper sizes are based on the ANSI scale. D-size paper for architectural plans is 24” x “36” inches (or 609.6 x 914.4 millimeters), while D-size paper for engineering plans is 22” x 34” (or 558.8 x 863.6 millimeters). There are, of course, other drawing paper sizes. So if you’re looking for D-size paper or any other blueprint paper size, feel free to look at what we have at Engineering Supply.