JDiskReport is a simple app that shows you where your hard drive space has gone. I have recently ran out of space on my Mac for the first time ever. I deleted quite a few files and I still have data on my hard drive that take space and that I don't need, but I couldn't know where they located. JDiskReport was of great help to me. The program can graphically show you how much space your folders and files take up so that you can take measures. In my case, after detecting where my big files were, I could regain a lot of hard drive space.
To show you where your space is, JDiskReport has to scan your hard drive first. This will take more or less time that depends on the size of your hard drive and the number of files that you have on your hard drive and the size of those files. While the software is scanning, you will see the elapsed and remaining time, but the remaining time estimate isn't very accurate. For example, the application scanned my 500-gigabyte hard drive in approximately 7 minutes and the estimated remaining time never went over 2 minutes.
After the scan was complete, I was shown a list of my directories on the left and a pie graph that demonstrated how much space each file/directory took on my hard drive. A nice feature is the Top 50 list, which shows the 50 largest files in the selected folder.
In short, JDiskReport is a great utility that has been really useful for me. It scans fast and it returns good data that can be used to free up hard drive space.