Costs Using Amazon EC2 & S3

Figuring out all the costs when hosting on EC2 using S3 storage can be tricky. This is break down of what you can approximately expect to pay using a few basic scenarios, such as a lamp server and S3 backups, with Amazon services. This will also compare the costs to what you would expect to pay if you want to do the hosting yourself.

To fully understand EC2 charges, you need to know the difference between the instance types and what they cost to best meet your requirements. For the purpose of this post I will summarize – I have converted the Amazon Compute Units into basic CPU power and will then detail the costs based upon each of these instances.





#1 Small Instance (32-bit):
1.7 GB memory
1 CPU (approx 1.0-1.2 GHz)
160 GB storage
Price: $0.10 per instance hour ($0.125 for Windows)

#2 Large Instance (64-bit):
7.5 GB memory
2 CPU (approx 2.0-2.4GHz per cpu)
850 GB storage
Price: $0.40 per instance hour ($0.50 for Windows)

#3 Extra Large Instance (64-bit):
15 GB memory
4 CPU (approx 2.0-2.4GHz per cpu)
1,690 GB storage
Price: $0.80 per instance hour ($1.00 for Windows)

#4 High-CPU Medium Instance (32-bit):
1.7 GB of memory
2 CPU (approx 2.5-3.0GHz per cpu)
350 GB of instance storage
Price: $0.20 per instance hour ($0.30 for Windows)

#5 High-CPU Extra Large Instance (64-bit):
7 GB of memory
8 CPU (approx 2.5-3.0GHz per cpu)
1690 GB of instance storage
Price: $0.80 per instance hour ($1.20 for Windows)

There is also a cost in terms of data transfer in and out of EC2 instances:
Data Transfer In: $0.10 per GB
Data Transfer Out: First 10 TB per Month $0.17 per GB

Note that EC2 storage does not count against your S3 storage, so you do not pay extra for that (160GB of S3 storage would be an extra $24/month).

All S3 charges will be based on the most expensive rates:
$0.15 per GB stored
$0.10 per GB in
$0.17 per GB out

Now that cost information is out of the way, let’s look at the scenarios.




S3 as a data backup option:

The first scenario we are going to deal with is using S3 strictly as a backup datastore. This implies that it is going to store files and upload a lot to a bucket, but not download.

100GB stored + 10GB/month in + 1GB/month out = $16.17/month

That seems very cheap for storage, but alas you pay this every month, so your cost at the end of the year will be more than $195! Also, note if you are writing 10GB to the bucket every month, your storage costs will go up $1.50 per month as you store more and more.

Considering the price of hard drives, you could have 3 or more 500GB hard drives for the same price. Storing on S3 is great for files you may want anywhere in the world without carrying a storage device of some sort, but it rather expensive. To store 1.5 TB on S3 will cost you $2700 for the year (excluding transfers!!!), a 1.5TB hard drive is $150! You do the math.

The calculation for the EC2 instances below is based on the following information:

EC2 Instance Hours (744) + 10GB IN + 10GB OUT

LAMP server | Rails Host:
Cheapest:
$74.40 + $1.00 + $1.70 =$77.10/month or about $920/year
Most expensive:
$595.20 + $1.00 + $1.70 = $597.90/month or over $7000/year

Windows Server:
Cheapest
$93 + $1.00 + $1.70 =$95.70/month or about $1100year
Most expensive:
$892.80 + $1.00 + $1.70 = $895.50/month or over $10000/year

So now you know what you can expect in terms of Amazon costs with a couple of setups. Minimum you are looking at $920 per year for your own dedicated virtual server on the Amazon cloud up to over $10000 per year. That is not horrible especially if you consider that they are providing the bandwidth, but it is expensive especially as you scale upwards.

To build a server with similar specs to the small instance will cost you much less than $900. For around $500 you would have a server better than that and have $400 to spend on your internet services for the year,and this hardware will be good for the next year as well one would hope.

I hope this information is useful to someone. As always please post any feedback. IMO if you like to lease things, then EC2 and S3 are for you. However if you would prefer a 1 time purchase and then depreciate the assets over time then you should maybe consider doing it yourself.

If you are looking for good scaling automation on Amazon check out Scalr.