When choosing a Perspex sheet (also known as acrylic), the right thickness depends on your specific project needs. Lightweight applications like poster frames, light diffusers, or protective covers typically require 2mm to 3mm thick sheets. These are easy to handle and cost-effective for indoor use.

For projects where the acrylic needs to hold some weight—like display stands, small shelving, or cabinet windows—5mm to 8mm is a better option. It offers more strength without adding excessive weight or cost.

If you’re working on a load-bearing or high-impact project, such as protective screens, aquariums, machine guards, or outdoor glazing, you’ll want to consider thicker acrylic sheets, typically 10mm, 12mm, or 18mm. The thicker the sheet, the more rigid and durable it becomes, but also heavier and more expensive—so it’s important to balance strength with practicality.

Still unsure what thickness of Perspex you need? Many suppliers provide thickness guides based on use case, or you can consult an expert before ordering.