Engineering drawing sheet sizes are based on the ISO A-series standard (ISO 216), used worldwide for technical drawings, CAD prints and manufacturing documentation.
Common sizes: A0 (1189 × 841 mm), A1 (841 × 594 mm), A2 (594 × 420 mm), A3 (420 × 297 mm) and A4 (297 × 210 mm).
The standard for drawing sheet sizes is the A series. The basic size in this series is the A0 size (1189mm x 841mm) which has an area of about 1 m2. The sides of every size in the series are in the ratio Sqrt(2) = 1.414 : 1 and each size is half the area of the next larger size.
Engineering drawings use ISO A-series paper sizes to ensure consistency in scaling, reproduction and layout. Each size maintains a constant aspect ratio of √2:1, allowing drawings to be scaled without distortion.
| Drawing Sheet Size | Size in millimetres | Size in inches |
| A0 | 1189 x 841 | 46.81 x 33.11 |
| A1 | 841 x 594 | 33.11 x 23.39 |
| A2 | 594 x 420 | 23.39 x 16.55 |
| A3 | 420 x 297 | 16.55 x 11.69 |
| A4 | 297 x 210 | 11.69 x 8.27 |
| A5 | 210 x 148 | 8.27 x 5.84 |
| A6 | 148 x 105 | 5.84 x 4.13 |
The ISO A-series paper sizes are based on a constant aspect ratio of √2:1. Each size is half the area of the previous size, making scaling between drawings simple and consistent.
Preferred Scales For Drawings...
The preferred scales are
1:1, 1:2, 1:5, 1:10, 1:20, 1:50, 1:100
Standard drawing scales are used to represent large or small objects clearly on paper. Choosing the correct scale ensures accurate interpretation of engineering drawings.
ISO 5457 defines standard drawing sheet layouts including trimmed and untrimmed sizes, ensuring compatibility across engineering drawings and printing systems.
| Designation | Trimmed Sheet | Drawing Space +/- 0.5mm | Untrimmed sheet +/- 2mm | |||
| - | Width (mm) | Length (mm) | Width (mm) | Length (mm) | Width (mm) | Length (mm) |
| A0 | 841 | 1189 | 821 | 1159 | 880 | 1230 |
| A1 | 594 | 841 | 574 | 811 | 625 | 880 |
| A2 | 420 | 594 | 400 | 564 | 450 | 625 |
| A3 | 297 | 420 | 277 | 390 | 330 | 450 |
| A4 | 210 | 297 | 180 | 277 | 240 | 330 |
Standard drawing sheet sizes follow the ISO A-series including A0, A1, A2, A3 and A4.
An A1 drawing sheet measures 841 × 594 mm.
A0 is the largest standard size, measuring 1189 × 841 mm.
The √2 aspect ratio allows drawings to be scaled up or down without changing proportions.
Common scales include 1:1, 1:2, 1:5, 1:10, 1:20, 1:50 and 1:100.
Summary: Engineering drawing sheet sizes follow the ISO A-series standard, providing consistent dimensions and scaling for technical drawings. Standard sizes such as A0 to A4 are widely used in mechanical and manufacturing design.