AWS S3 pricing calculator

# TB usage at which pricing changes
s3_tiers = %w{50 100 500 1000 5000 1000000000}.collect {|x| x.to_f}

# Cost per GB/month for each of the above tiers
s3 = %w{0.15 0.14 0.13 0.105 0.08 0.055}.collect {|x| x.to_f}
s3_reduced = %w{0.1 0.093 0.087 0.07 0.053 0.037}.collect {|x| x.to_f}

# ebs is always 0.10/GB per month
ebs = %w{0.1 0.1 0.1 0.1 0.1 0.1}.collect {|x| x.to_f}

# google data is 0.17/GB/month

# rackspace files is 0.15/GB/month

# Using ec2 instances for storage
# large = 850GB at 0.34/hr = (0.34 * 24 * 31) / 850 = 0.2976 per GB/month
# reserved large 1 yr = 850GB at 0.12/hr with $910 fee = ((0.12 * 24 * 31) + (910 / 12)) / 850 = 0.1933 per GB/month
# reserved large 3 yr = 850GB at 0.12/hr with $1400 fee = ((0.12 * 24 * 31) + (1400 / 36)) / 850 = 0.1497 per GB/month

def calc_usage(usage, tiers, cost)
  total = 0.0
  tiers.each_with_index do |t, i|
    if usage <= t
      total += cost[i] * usage * 1000
      break
    else
      total += cost[i] * t * 1000
      usage -= t
    end
  end
  return total
end

tb_used = 1000

puts "Monthly costs for #{tb_used}TB"
puts "S3: #{calc_usage(tb_used, s3_tiers, s3)}"
puts "S3 Reduced: #{calc_usage(tb_used, s3_tiers, s3_reduced)}"
puts "EBS: #{calc_usage(tb_used, s3_tiers, ebs)}"