You’ll see craft foam referred to by a few common names, depending on the project and material:

• EVA foam – flexible sheets popular for costumes, props, and DIY patterns.
• Foam sheets – thin, easy-to-cut sheets used for kids’ crafts and signage.
• Foam board – a rigid panel with a foam core, great for displays and mounting.
• Polystyrene foam – lightweight blocks, balls, and discs for modeling and floral bases.
• Upholstery foam – polyurethane foam used for seats, cushions, and padding.

If you’re browsing, try filters like Crafting or Upholstery to zero in on the right type and thickness.

In crafts, “foam” generally refers to lightweight, airy plastics formed with tiny bubbles. Different foams offer different benefits:

• EVA foam sheets are flexible and shapeable for props, masks, and patterns.
• Polystyrene foam comes in rigid shapes (blocks, discs, balls) for modeling and floral designs.
• Upholstery foam (polyurethane) is used for cushioning projects like benches and seat pads.
• Foam board provides a sturdy surface for displays, signs, and school projects.

When you shop, check dimensions, thickness, and firmness notes (like “soft,” “medium,” or “firm”). Choosing a foam that matches your project’s flexibility, shape, and support needs can make crafting easier and results more consistent.

Three widely used foams you’ll find for craft projects include:

• EVA foam sheets – Flexible, smooth, and easy to cut or heat-shape for costumes and props.
• Polystyrene craft/floral foam – Rigid forms (blocks, balls, discs) for modeling, wreaths, and arrangements.
• Polyurethane upholstery foam – Cushioning pads and slabs for seats, benches, and padding.

Each type serves a different goal: EVA for wearable and detailed builds, polystyrene for lightweight structure, and upholstery foam for comfort and support. Browse by size and thickness to match your project, and review product details for firmness or density notes that can help you dial in the feel.

A few simple techniques can help you get cleaner cuts:

• Mark first: Use a straightedge and light pencil or chalk lines.
• Use the right blade: A sharp craft/utility knife works well for thin sheets; a serrated or electric carving knife can help with thicker upholstery foam.
• Make shallow passes: Several light cuts are often smoother than one deep slice.
• Support the work: Cut on a stable surface or cutting mat to prevent tearing.
• Go slow: Avoid forcing the blade; let it glide to reduce jagged edges.

For rigid polystyrene shapes, light pressure and multiple passes can reduce crumbling. Always cut away from yourself and consider protective gloves for added control.

Density describes how much material is in the foam per unit volume. Higher-density foams generally feel more substantial and may offer longer-lasting support, though density alone doesn’t determine firmness.

ILD (Indentation Load Deflection) indicates firmness: it’s the force needed to compress the foam to a set percentage. Higher ILD numbers typically feel firmer, while lower numbers feel softer. Many cushion foams list both.

When choosing foam, consider intended use (e.g., seat vs. back cushion), thickness, and cover materials. Checking product details for both density and ILD can help you balance comfort and support, but preferred feel can vary by project and personal preference.