Oversized carpets: a frequently asked question is whether furniture should be placed on top of the carpet in a seating area or not. Even though there are no rules regarding this we suggest that you don’t and rather place furniture +/- 10cm away from the carpet edges. This will showcase the carpet much better, make cleaning easier and there will be less damage to the carpet if the furniture is heavy.
The standard size: In a standard seating room with standard sized furniture a 300x200 carpet will fit perfectly, unless you have limited space in which case you might opt for a 250x150. An important feature to consider is the size of the coffee table. The carpet should stick out at least 50cm on all sides. Furniture can either be placed next to the carpet or partially on top. It really depends on what makes the room look great and lets the carpet breathe.