Standard hard plastic/nylon casters will absolutely scratch hardwood floors. The damage can happen within days of regular use. Replace them with soft rubber or polyurethane casters immediately. Even with soft casters, a chair mat is recommended for heavy use, as trapped debris in wheels can still cause scratches.

Soft rubber/polyurethane casters work on both surfaces, but they roll harder on carpet. Rollerblade-style casters are the best universal option - they're smooth on hard floors and still roll reasonably well on low-pile carpet. For high-pile carpet, you may want dedicated hard casters or a chair mat.

Vinyl and LVP flooring is soft and prone to permanent denting from concentrated pressure. Your full body weight plus chair weight (200-300+ lbs) is distributed over just 5 small caster wheels, creating enormous pressure per square inch. A chair mat distributes this weight over a larger area. Unfortunately, existing dents in vinyl rarely recover fully.

Minimum: 36" x 48" (standard size). Recommended: 46" x 60" for more rolling room. Measure your chair's movement area - you should be able to roll freely without casters leaving the mat. For L-shaped desks, consider a larger mat or custom cut. Many people underestimate how much they roll throughout the day.

For most users, yes. Rollerblade-style casters are quieter, smoother, more durable, and safe for all floor types. They cost $25-50 for a set of 5 and are one of the best upgrades you can make to any office chair. They're especially recommended if you move frequently throughout the day or have sensitive flooring.