A pneumatic staple gun is the best staple gun for heavy-duty DIY projects like carpentry, flooring, and upholstery. They use compressed air to powerfully push staples into materials like hardwood, and they are known for both speed and accuracy.

Almost any fine wire and medium wire staples can be used for upholstery, depending on your fabric. 20 and 22 gauge staples are the most common staples for upholstery. #7 series staples 22 Gauge, #8 (80) series staples 20 Gauge, and T-50 series staples 20 Gauge are commonly used for these applications.

Fine wire staples range from 20-22 gauge. These staples are ideal for upholstery projects, cabinets, fine wood trim, batten strips, picture frame fitting, wood baskets, plastic parts, molding and furniture assembly.

There are pneumatic staple guns, electric staple guns, and hand-held staple guns. Any of those could work, but the ones that I feel work best for upholstery are the pneumatic staple guns. The difference is the pneumatic staple guns have more power.