Amazon EC2 Auto Scaling allows you to scale your Amazon EC2 capacity up or down automatically according to conditions you define. With Amazon EC2 Auto Scaling, you can ensure that the number of Amazon EC2 instances you’re using increases seamlessly during demand spikes to maintain performance, and decreases automatically during demand lulls to minimize costs. Amazon EC2 Auto Scaling is particularly well suited for applications that experience hourly, daily, or weekly variability in usage. Amazon EC2 Auto Scaling is enabled by Amazon CloudWatch and available at no additional charge beyond Amazon CloudWatch fees.