One of the podcasts I listen to every week recently crossed the 100.000 regular listener mark. Quite a number and it made me think how much it costs to deliver that podcast four times a month to 100.000 recipients!?
Let's do the maths: Let's say the podcast audio file has a size of 50 MB. Four times a month makes that 0.2 GB x 100.000 listeners, so the total volume to deliver is 20.000 GB or 20 TB. Now how much does it cost to deliver 20 TB of data? Large cloud providers have special services for content delivery and Amazon's CloudFront service, to make a practical example, charges 0.10 cents per GB on average for that kind of data volume. In other words, delivering 20.000 GB per month costs $2000 a month plus the cost of the virtual or physical web server behind the CloudFront service. When you look at it from a listener's point of view, it costs half a cent to deliver a single episode or two cents a month per listener.
Interesting numbers! One thing I didn't factor in is that the podcast is also available as videocast in HD as I have no idea what their ratio is between those who listen vs. those who watch the video stream.
Update: A reader sent me an email today with a link to an alternative hosting provider with quite different prices. They are asking for €2 per TB, i.e. €40 = $53 instead of the $2000 calculated above when using Amazon's CloudFront service. I'm a bit baffled, that's quite a difference.
I wonder how many of those identical file copies will be delivered out of web caches and won’t count to the overall volume seen at the original server.