INSTRUCTIONS  

  1. Upload your desired blueprint by clicking the "Upload PNG" button located on the top right of the page.

  2. Move and set the green calibration (CAL) line to the right length.

  3. In the right side panel, enter the scale of the calibration line to 3 decimal places (in metres).

  4. Click either "Perimeter" or "Surface Area" mode buttons at the top bar.

  5. Position your mouse crosshair to the desired sections of your blueprint.

  6. Left-click with your mouse to start drawing lines/areas over your blueprint.

  7. There are two ways to go back to "Observe" mode:

    • via clicking the "Observe" button at the top bar.

    • via pressing the ESC key on your keyboard.