Customized foam sizes can be obtained through several methods, depending on your requirements and intended use.

• Foam Retailers or Manufacturers: Many foam retailers or manufacturers offer custom cutting services. You can contact them and provide your desired dimensions, and they will cut the foam according to your specifications. This can be done in-store or online, depending on the company.

• Local Upholstery or Fabric Stores: Upholstery and fabric stores often offer foam cutting services for customers who need foam for furniture cushions or other projects. They may have equipment to cut foam to the exact size you need.

• Online Foam Retailers: There are numerous online retailers specializing in foam products. Many of them offer customizable options where you can input the dimensions you need, and they will cut the foam accordingly before shipping it to you.

• Specialty Foam Cutting Services: Some companies specialize in foam cutting for specific industries or applications, such as packaging, insulation, or theatrical props. These companies may offer more advanced cutting techniques and a wider range of foam types.

• DIY Foam Cutting Tools: If you're comfortable with DIY projects, you can invest in foam cutting tools such as hot wire cutters, foam saws, or electric knives. With the right tools and some practice, you can cut foam to your desired size and shape at home.