CloudWatch metrics cost calculation

Understanding CloudWatch metrics cost calculation for AWS services

This document explains how the cost of CloudWatch metrics is calculated in AWS when retrieving data at a five-minute interval for multiple metrics over a month.

Step-by-step cost calculation

1. Requests per metric

When retrieving a metric at a five-minute interval, the number of requests per metric is calculated as follows:

Each metric request is made every five minutes. There are 60 minutes in an hour and 24 hours in a day. Therefore:
  1. Metric requests per hour: 60 / 5 = 12
  2. Metric requests per day for each metric: 12 × 24 = 288
  3. Metric requests per month for each metric: 288 × 30 = 8,640
Thus, for one metric, the total number of metric requests in a month is 8,640.

2. Total requests for 20 metrics

When retrieving 20 metrics, the total number of metric requests is calculated as follows:
  1. 8,640 requests per metric × 20 metrics = 172,800 metric requests per month
So, for 20 metrics, the total number of metric requests in a month is 172,800.

3. Cost calculation

AWS charges $0.01 per 1,000 metric requests for GetMetricData.

Therefore:
  1. Chargeable metric request units: 172,800 / 1,000 = 172.8
  2. Total cost: 172.8 × $0.01 = $1.728
Total expected cost

For 20 metrics retrieved at a five-minute interval over a month, the estimated cost for GetMetricData requests is approximately $1.73.
Notes
If you're using custom metrics or need high-resolution metrics (which are billed differently), that could change the price. But for standard metrics, $1.73 would be your estimated cost.
Help resource: Metric Profile