There is one more "gotcha" if you dig deeper. That is the drop in EC2 prices and Amazon in general has been vague about passing on the benefits of price drop to old reservations ( https://forums.aws.amazon.com/message.jspa?messageID=325153 ) . We even thought about adding speculative price drop and then do the comparison, but dropped the idea. It will be interesting to hear the take of HN community on this ..
Quote from the page above
"
Light and Medium Utilization Reserved Instances also are billed by the instance-hour for the time that instances are in a running state; if you do not run the instance in an hour, there is zero usage charge. Partial instance-hours consumed are billed as full hours. Heavy Utilization Reserved Instances are billed for every hour during the entire Reserved Instance term (which means you’re charged the hourly fee regardless of whether any usage has occurred during an hour). "
Thanks for the feedback. We are doing the "t1.micro, m1.small .."translation right now. (Edit : changes pushed)
X axis value seems to be some browser issue. On some browsers it shows up only at reduced zooms. Will fix it.
Also, we are not trying to replace AWS cost calculator. It was more like putting our own dog food out to answer the question, that at what point/usage is the reserved instance better than on demand.
