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FAQ

Frequently asked questions about Commitment Simulator.

Commitment Simulator vs. AWS Cost Explorer​

How is Commitment Simulator different from AWS Cost Explorer recommendations?​

AWS Cost Explorer provides a recommended hourly commitment with limited visibility into how that number was derived or how costs change at other commitment amounts.

Commitment Simulator shows the entire cost landscape, a full curve from zero commitment to maximum, the exact point where savings peak, and where overcommitment begins and costs start rising again.

What can I see in Commitment Simulator that I can't see in AWS?​

  • The complete cost curve from $0/hr to maximum commitment

  • A breakdown of covered, uncovered, and wasted spend at every hourly commitment

  • All term and payment options compared side by side in a single table

  • Flexsave for Compute costs as a baseline for comparison

  • Interactive tooltips with exact dollar savings at any point on the curve

Data and coverage​

How often is the data updated?​

Data is updated monthly, on the 5th day of each month. This ensures that all Cost and Usage Report (CUR) data from the previous month is available for accurate processing.

What data does Commitment Simulator use?​

Hourly AWS billing data from DoiT's billing integration. Commitment Simulator does not access AWS accounts directly and does not make any changes to your infrastructure.

Does Commitment Simulator account for Savings Plans or Reserved Instances I've already purchased?​

Yes. Commitment Simulator excludes usage already covered by existing Savings Plans and Reserved Instances. It only analyzes the remaining on-demand usage that is still eligible for a new Savings Plan. The optimal commitment it shows is the additional amount you could commit on top of the coverage you already have.

Why do I see "We're compiling your data"?​

Billing data is still being processed. Check back in a few hours. See Status messages and page states for more information.

Understanding results​

Should I purchase at the optimal commitment?​

Not necessarily. The optimal commitment is the hourly amount that would have minimized costs during the selected month. It is backward-looking, not a forecast.

Committing slightly below the optimal often yields comparable savings with significantly lower risk. See Optimal commitment for more information.

For Compute and SageMaker, 3-Year No Upfront balances savings depth with financial flexibility: deeper discounts than 1-year terms with no upfront capital required.

For Database, 1-Year No Upfront is highlighted instead (the only available term and payment combination).

The Recommended label identifies the best historical result; it is not a directive to purchase.

What's the difference between "Savings available" and "No savings"?​

  • Savings available: purchasing a Savings Plan would be cheaper than on-demand and Flexsave (when active).

  • No savings: a Savings Plan would not reduce costs below what you're already paying.

Why is a Savings Plan type disabled in the selector?​

The payer account had no usage for services covered by that type during the selected month, or no hourly commitment would produce savings.

Flexsave for Compute​

How does Commitment Simulator relate to Flexsave for Compute?​

Flexsave for Compute is DoiT's managed savings solution. It reduces costs automatically with no long-term commitment. Commitment Simulator shows whether purchasing self-managed Savings Plans would save even more by including Flexsave costs as a baseline in the summary table and charts.

If Flexsave is active, why would I consider Savings Plans?​

Self-managed Savings Plans can offer deeper discounts for stable, predictable workloads, with a 1- or 3-year lock-in that cannot be canceled.

Commitment Simulator shows the exact dollar difference, making it possible to evaluate whether the extra savings justify the commitment risk.

Risk and purchasing​

Can I cancel a Savings Plan after purchasing it?​

Almost never. AWS Savings Plans are a long-term commitment: the committed hourly rate is due for the full 1- or 3-year term.

AWS does allow returns under strict conditions. The plan must have an hourly commitment of $100 or less, be returned within 7 days of purchase and within the same calendar month, and you have a limit of 10 returns per management account per calendar year. Outside of those conditions, there is no way to reduce or exit a commitment. Treat every purchase as a lock-in.

How do I minimize commitment risk?​

  • Commit below the optimal point: this leaves room for usage fluctuations.

  • Start with a No Upfront commitment to avoid tying up capital.

  • Reassess each month and add incremental commitments as needed.

See Optimal commitment: Best practices for details.

Does Commitment Simulator purchase Savings Plans for me?​

No. Commitment Simulator is an analysis tool. It shows the full cost curve, the optimal commitment, and savings at every commitment level, so you can make an informed decision.

Payer accounts​

What is a Management Account?​

A management account is the primary account that centrally manages billing for all linked member accounts. The usage and costs from each member account are aggregated and billed to the management account.

By default, Savings Plans purchased through the management account are shared across all member accounts, helping optimize overall costs (although sharing can be disabled if needed).

I have multiple payer accounts. Does Commitment Simulator analyze them separately?​

Yes. AWS Savings Plans are scoped to a management payer account; a plan purchased under one MPA does not apply to usage in another. Use the MPA ID selector to switch between payer accounts and analyze each one independently.

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