RAID Storage Calculator

Work out the usable capacity, redundancy overhead and fault tolerance of a disk array for each common RAID level. Enter the number of disks and the size of each, pick a level (0, 1, 5, 6, 10, 50 or 60), and get usable space, raw capacity, parity/mirror overhead, how many disks can fail at once, and minimum-disk validation. Useful when sizing a NAS or server array. Pure arithmetic — no account of rebuild time or real-world formatting overhead. Everything runs locally in your browser.