Savings Plan Comparison Calculator

Work out savings plan comparison instantly with clear inputs, formula shown and shareable results.

About Savings Plan Comparison Calculator

A savings plan discounts a committed hourly spend, so the blended discount is the headline rate multiplied by coverage. Committing 70 percent at a 28 percent discount yields only 19.6 percent overall — which is deliberate, because committing 100 percent of a variable workload guarantees paying for capacity you stop using.

Formula

Blended saving

committed = on-demand x coverage; new spend = committed x (1 - discount) + uncovered; effective discount = saving / on-demand

Worked example

With the default values below, Savings Plan Comparison Calculator returns Monthly saving of $7,840.00. Change any input above and every figure here is recalculated in your browser.

Inputs used

On-demand monthly compute spendminimum 0: 40,000
Share of spend to commitaccepts 1–100 %: 70 %
Savings plan discountaccepts 0–80 %: 28 %
Commitment termaccepts 1–3 years: 1 years

Results

Monthly saving: $7,840.00
New monthly spend: $32,160.00
Saving over the full term: $94,080.00
Effective blended discount: 19.60%

Step by step

1Values used
2Blended saving
3Monthly saving= 7,840.00
4New monthly spend= 32,160.00
5Saving over the full term= 94,080.00
6Effective blended discount= 19.60

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

What coverage is safe?

Commit to your reliable baseline, typically 60 to 80 percent of steady-state spend. Anything seasonal or growth-dependent should stay on demand or spot.

Are three-year terms worth it?

The extra discount is significant but so is the risk: architecture changes, instance-family shifts and workload migration over three years can leave the commitment stranded.