How Heavy Is A Petabyte?

Updated November 2013

It’s sometimes hard to visualise just how much disk technology has advanced in the last 30 years. There is an excellent graphic on the Gizmodo website which successfully portrays: “How Large is a Petabyte?” leading Mark Coleran (Gridiron Flow fame) to ask “How much does a Petabyte weigh?”

Here is my take on just how heavy 1 Petabyte of disk drives was in 1980 and is today. (Disks only, not taking into account server chassis, racks, power and airco units to support it! UPDATE: also all information, the weights, garnered via internet search and wikipedia ..) If you want to know how much a Petabyte costs, look no further:


The answer from 1980:

And the answer today (2009!):

One Petabyte of Western Digital Caviar Green

One Petabyte of Western Digital Caviar Green


I guess this will be a living blog post given that drives are increasing in capacity every two seconds! With the 3TB internal drive hitting the streets I have put together another image (quick and dirty apparently!):

UPDATE 2 – 4TBs are here (2012)

UPDATE 3 – 6TBs are here (2013)

Knew it would not be long! A petabyte of disk now weighs as little our very own Petaman!


If you would like more information on how to implement a management free nearline storage platform that scales to multiple petabytes then please  contact us:

The View from OM

Disk efficiency, capacity and usability has all increased enormously in the last 3 decades making it more and more feasible to protect/archive content on disk long term. When companies like EMC currently have over 2000 clients storing over 1 Petabyte of content it makes you think that 1 Petabyte is not that large an amount after all.

Object Matrix Storage Team

p.s Used purely marketing figures in the calculations (1kb == 1000bytes) .. obviously using real, tech numbers (1024) we would be looking at more disks. I

look forward to the day we can all talk in 1024.

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