Find out what changed in the cloud bill — Cost Explorer

Your goal

Investigate a cost increase by comparing useful groups and time periods.

Why this matters

This month’s recorded cost is higher than expected. You will choose a fair comparison, find the main contributor, and check whether usage or another factor explains the difference.

Words you will use

A cost group combines related charges, such as one service. A filter narrows the view. A cost metric defines how amounts are calculated. Usage measures how much of a resource was consumed.

How to proceed

Read each situation and choose an answer. The lesson explains the result. Try again if needed, then continue through all three decisions and finish the tour.

1. Compare like with like

One chart shows a full previous month and another shows only the first week of this month. Comparing the totals directly could mislead the team.

What should stay consistent?

Time range, scope, and the chosen cost metric.

Choose comparable periods and understand the cost metric and filters. Current data can still be incomplete. State those limits so the team does not confuse a partial period or different calculation with a real change.

The comparison has a fair and understandable basis.

Comparable periods + consistent metric and scope

2. Find the main contributor

The total increased, but the team does not know which service or account drove the change. Choose a useful first breakdown.

How should you narrow the view?

Group by service or account, then filter the largest relevant change.

Start with a useful grouping, then narrow to the area that explains the change. Compare related usage and configuration evidence. Cost Explorer helps locate a pattern; the explanation may require additional operational context.

The investigation focuses on the strongest cost contributor.

Total change → service/account grouping → focused filter

3. Check the explanation

A service’s cost rose, but usage, pricing choices, credits, and timing can affect the number. The team needs evidence before changing production.

What should happen next?

Compare usage and relevant changes, then test a targeted improvement.

Look for a supported explanation and confirm the workload’s purpose before acting. A useful cost change preserves needed behavior. Measure the result over an appropriate period and account for reporting delay.

The team chooses a targeted action with a way to measure it.

Cost pattern + usage/context → tested change → follow-up

Practice, then check your understanding

In the interactive tour, make each decision before seeing the outcome. Wrong answers receive coaching, and replay gives you a fresh attempt without duplicating earned XP.

Read the official AWS documentation for service behavior and production details.