AWS RDS pricing calculator guide: estimate your bill

Start with the database configuration you expect to run: engine, Region, instance type, deployment, storage and hours. Price every configuration separately, then add them together. That gives you an On-Demand budget you can use before deciding how much to commit.

An AWS RDS pricing calculator can price those inputs. A commitment decision also needs the hours when the databases run. In the worked analysis below, the same monthly usage produces either a $57.67 saving or a $29.57 increase with one Reserved Instance.

Build the On-Demand estimate first

In AWS Pricing Calculator, create an estimate and add Amazon RDS. Use a separate entry when the engine, Region, instance type or deployment changes. Groups let you keep regional stacks or cost centers together. Save the estimate so someone else can check the same inputs.

For a fleet across three Regions, a simple planning sheet might look like this. These are example configurations, not sizing recommendations.

Choose the actual Multi-AZ deployment in the calculator. A DB instance with one standby and a Multi-AZ DB cluster are different configurations. Add read replicas as their own resources; check the quote before adding standby capacity a second time. Our Single-AZ and Multi-AZ cost guide covers that choice.

Include storage capacity and performance, billable backups, data transfer and any services you use, such as RDS Proxy or Extended Support. Leave a cost out only after checking that it does not apply. Stopped instances still have storage charges and may have billable backup storage.

What does one RDS database cost per month?

A MySQL db.r8g.large Single-AZ instance in US East (N. Virginia), running for a 730-hour planning month with 200 GiB of gp3 storage, comes to $197.47 before additional charges at the rates checked for this article.

This is a configuration estimate, not a measured bill. It excludes extra storage performance, billable backups, transfer, Proxy, CPU credits, Extended Support, monitoring, AWS Support, tax, account discounts and credits. A 730-hour average month is useful for planning; an actual calendar month has a different number of hours.

If you already run the workload, compare the estimate with your billed usage. Use AWS’s in-console Pricing Calculator when you need to model eligible account discounts and existing commitments. Keep the public-price estimate as a separate baseline so the comparison stays understandable.

How timing changes the reservation result

Consider two of those MySQL databases, each running for 365 hours in the same 730-hour model. Each keeps its 200 GiB storage volume for the whole period. Their combined On-Demand compute is $174.47 and storage is $46, for a total of $220.47.

Now add one matching, one-year No Upfront RI at $0.160 per hour. Its compute obligation is $116.80 for the modeled month. Assume there is no other matching usage or existing commitment, and compare two schedules:

With staggered schedules, exactly one database runs in every hour. The reservation’s discount can cover all 730 database-hours. With overlapping schedules, both run in the same 365 hours. One reservation covers one instance’s usage in those hours; the other instance remains On-Demand. The reservation is unused for the other 365 hours.

The RI’s hourly compute rate is about 33% lower, but 50% utilization makes the overlapping case more expensive. At these rates, the compute break-even point is $0.160 ÷ $0.239 = 66.95% utilization, or roughly 489 used reservation-hours in a 730-hour month.

That threshold concerns this one reservation. It does not tell you how many reservations to buy across a fleet. Storage cancels out of this particular comparison because it is identical in both cases.

Planning commitments for several Regions? Book an RDS product demo to see the review workflow. Account-specific figures require a separate billing and usage review.

Check matching usage before buying

Repeat the hourly check within each group of usage that can receive the same discount. An RDS RI in N. Virginia cannot cover a database in Ireland. MySQL and PostgreSQL do not become interchangeable because their bills sit in the same account. Size flexibility has engine and instance-family rules, too.

A steady company-wide bill can therefore hide unused commitments in one Region and uncovered usage in another. Keep the Region, engine, instance family and existing coverage visible when you review a proposal.

Before purchasing, ask for the hourly utilization assumption, the remaining On-Demand cost and the cost if your planned migration happens. Compare the full upfront and recurring obligation. A missing RI quote is a reason to verify the offering with AWS, not a reason to assume a discount.

If engines, families or Regions are likely to change, also evaluate Database Savings Plans. AWS describes them as a one-year hourly-spend commitment that can follow eligible usage across those attributes. They cannot discount the same usage already receiving an RDS RI benefit, and unused commitment remains a concern. Our RDS RIs vs Database Savings Plans comparison explains the tradeoffs.

What a Usage.ai review should make clear

Usage.ai reviews billing, usage patterns and existing commitments to identify eligible savings. Evaluation starts with read-only access. Your team can approve recommendations in Copilot or allow Autopilot to make eligible purchases within approved controls. Commitments remain in your cloud account.

Compare the projected AWS saving with Usage.ai’s fee and the amount you expect to keep. The current pricing page explains the savings-based managed service.

Flex Insured Commitments include Cashback for eligible unused value, subject to terms. Current eligibility requires 30 consecutive days of underutilization, and protection ends when the managed service ends. Cashback does not cancel the AWS commitment. Read the Flex program details when comparing proposals.

Questions about RDS estimates

Additional source notes: AWS Pricing Calculator, Getting started and Pricing; Amazon RDS, On-Demand DB instances; AWS Database Savings Plans pricing; Usage.ai homepage, pricing and Flex documentation. Technical rules and the quoted prices were checked November 5, 2026. The calculations are illustrative and do not predict account-specific savings.