GCP Sustained & Committed Use Discount Calculator

No, and this is the most expensive misunderstanding in Google Cloud commitment planning. Usage covered by a commitment bills at the committed rate and earns no sustained-use discount. So the value of a commitment is the difference between the two discounts, not the commitment percentage. On a self-serve (online) billing account, a workload already running all month on an N1 machine earns a 30% sustained-use discount automatically; buying a 28% one-year flexible commitment for it is worse than doing nothing. Invoiced accounts get no sustained-use discount, so there a commitment is measured against list price.

Sustained use discounts apply only to self-serve (online) billing accounts. Invoiced accounts get none. Where it applies, it is applied per quarter of the month, not as a flat rate on the total. Each quarter a resource runs is discounted at its own multiplier, and the discount you see is the average of the quarters you used. On the 30% band the four quarters bill at 100%, 80%, 60% and 40% of on-demand, so a full month averages 30% off, but half a month averages only the first two quarters, which is 10%. The curve is convex, so the final quarter of uptime is worth far more discount than the first.

N1 general-purpose machine types (predefined and custom), N1 sole-tenant nodes, the M1 and M2 memory-optimized machine types, the f1-micro and g1-small shared-core types, and GPUs attached to N1 machines reach 30%. N2, N2D and C2, including their sole-tenant nodes, cap at 20%. Series that are not on Google's list, including E2, N4, C3 and C4, earn no sustained-use discount at all. It is worth checking against the English documentation: the translated version of that page orders the two columns differently, and reading it there gives exactly the wrong mapping.

Yes. A compute flexible commitment is a fixed hourly fee for the whole term, and a resource-based commitment is billed monthly for the committed resources, in both cases whether or not anything runs. So a fleet that is off half the month pays for the commitment all month, and the commitment only pays once the machines run enough of the month to use it. This calculator charges every committed hour and reports the uptime a commitment needs to pay off.

A compute flexible CUD is spend-based: you commit to an hourly amount of spend for the billing account, and it applies to eligible Compute Engine, GKE and Cloud Run usage in any project or region. For the N1, N2, N2D, E2, N4, C3 and C4 machines priced here, the published rates are 28% for one year and 46% for three; Cloud Run request-based billing gets 17%, and M-series machines get nothing for one year. Google moved every billing account to its new spend-based model by February 6, 2026: the hourly amount you commit is the discounted spend, and covered usage bills at the discounted price rather than at list price less a credit. A resource-based CUD is Compute Engine only and commits you to specific vCPU and memory in a specific region, in exchange for a deeper discount. Google lists it per machine type and region: most are 37% for one year and 55% for three, but some regions differ (N1, N2 and N2D in us-east4 and us-west4 are about 40% and 57%), and memory-optimized series go up to 70%.

You can't cancel a commitment after you buy it. A resource-based commitment is for one machine series in one region and is billed monthly whether or not you use it, so an N2 commitment keeps billing if you move the workload to N4 or C4. A compute flexible commitment is a spend amount: it follows your eligible spend across machine series, regions and projects, and also covers GKE and Cloud Run.

From Google's Compute Engine pricing page, which lists every predefined machine type in every region with its on-demand and committed rates. This calculator reads that list for the N1, N2, N2D, E2, N4, C3 and C4 series, checks every rate against the page's own monthly figures, and shows the date it was read. They are list prices: if you have a negotiated discount, or use custom machine types or another series, choose My own price and enter your hourly rate.