Thinner mats (economy or regular) are usually sufficient.
Look for a smooth-backed mat. Spiked mats will scratch or mar hard surfaces. Regular cleaning under the mat is essential to prevent trapped grit from acting like sandpaper. CHAIR MATS
These require a cleated (spiked) backing to "grip" the carpet and prevent shifting. Thinner mats (economy or regular) are usually sufficient
The backing of the mat is the most critical feature to match to your flooring. CHAIR MATS
Requires extra thick mats with longer spikes to prevent "dimpling," which is when the chair sinks into the mat, making it impossible to roll. 2. Comparison of Materials Chair Mat Buyer's Guide - MyBinding.com