The reigning constructors' champions have been testing alongside the other F1 teams in Barcelona this week, with Webber posting the 13th fastest time and world champion Sebastian Vettel coming fifth.
The Australian told reporters: "This was a good test for us in terms of everybody's role in the team.
"We need to improve, we need to do better this year as a team and we are focusing very hard on ourselves and achieving that. The boys did a very good job today, the best I've seen them work for a long time.
"In 2011 and 2012, we were not super reliable and I could have done better in certain races. But ultimately, we can do better all together, my side, the team side, all of us together. That will mean a strong performance for us in '13."
Webber finished sixth in the drivers' standing in 2012.