By Stephen Milner · UtilityForge · Last reviewed: May 2026
This tool calculates estimated on-demand costs for AWS EC2 instances across four instance families, eleven regions, and four operating systems. You pick your instance type, region, OS, expected monthly hours, and number of instances. The tool gives you hourly, monthly, and annual cost figures plus a transparent pricing breakdown.
It is aimed at developers, startups, and DevOps teams who need a fast sanity-check before committing to a cloud architecture. No AWS account or sign-in is required.
T3: Burstable General Purpose. The lowest-cost option for workloads that do not need sustained CPU. Good for development environments, low-traffic web servers, and small databases. CPU credits accumulate when utilization is below baseline and are consumed during spikes.
M6i: General Purpose. The standard workhorse for production workloads. Balanced CPU and memory, consistent full-core performance with no burst limitations. Appropriate for application servers, mid-size databases, and backend APIs with predictable load.
C6i: Compute Optimized. Higher CPU-to-memory ratio. Suited to batch processing, scientific modelling, dedicated game servers, and encoding pipelines where raw compute throughput matters more than RAM headroom.
R6i: Memory Optimized. High RAM-to-CPU ratio. Designed for in-memory databases (Redis, Memcached), real-time analytics, SAP HANA, and any workload whose working set must fit entirely in memory.
I3: Storage Optimized. NVMe SSD local storage included. Suited to high-IOPS workloads: NoSQL databases, search indexes, data warehousing, and log analytics where low-latency disk access is critical.
The tool derives costs from AWS on-demand Linux pricing for us-east-1, then applies two multipliers:
Reserved Instances and Savings Plans can cut on-demand costs by 30–72% for steady-state workloads. A one-year, no-upfront Reserved Instance typically saves around 30–40%. A three-year all-upfront commitment can cut costs by more than 60%.
Spot Instances offer up to 90% off on-demand for fault-tolerant, interruptible workloads such as batch jobs, stateless web tiers behind a load balancer, and CI/CD workers.
Right-sizing is often the largest single saving. Most teams over-provision. Start with a smaller instance, monitor CPU and memory utilisation for two weeks, then resize. AWS Cost Explorer has a built-in right-sizing recommendation engine.
Graviton instances (M7g, C7g, R7g) use AWS-designed Arm processors and typically cost 20% less than their x86 equivalents for comparable performance. If your application runs on Linux and your dependencies support Arm, Graviton is worth evaluating.
On-demand pricing. Pay per second, no commitment. Highest per-unit cost but maximum flexibility. Use for unpredictable workloads or initial sizing before you understand usage patterns.
vCPU. A virtual CPU. Each physical core is hyperthreaded into two vCPUs, so a 4 vCPU instance corresponds to two physical cores on the host.
EBS-optimised. All current-generation instances are EBS-optimised by default, meaning network storage throughput is dedicated and not shared with general network traffic.
Utilization (hours per month). 730 hours equals 24/7 operation for a 30.4-day month. 160 hours approximates a standard 5-day, 8-hour business schedule.
The base prices come from AWS on-demand Linux rates for us-east-1 as published in early 2026. Regional and OS multipliers are approximations derived from historical AWS pricing patterns rather than live API calls. For exact figures, use the AWS Pricing Calculator. This tool is designed for quick sanity-checks during architecture planning, not for finance-grade cost modelling.
AWS operates data centres across the world with different infrastructure, power, and real-estate costs. US East (N. Virginia) and US West (Oregon) are the cheapest because they are the oldest and largest AWS regions with the most economies of scale. Asia Pacific (Tokyo) and South America (São Paulo) carry premiums of 20–43% over the baseline.
The Windows Server license fee is bundled into the AWS on-demand rate. For a t3.medium, the Windows price is roughly double the Linux price. The ratio is less extreme for larger instances because the base compute cost grows faster than the flat license fee. The multiplier used here (×2.10) is an average across small-to-medium sizes; exact figures vary by instance.
Several cost components are outside the scope of this estimator:
T3 instances use a credit-based CPU model. They accumulate credits during low-activity periods and spend them during bursts. If your application sustains high CPU for extended periods, T3 instances throttle once credits run out, and you must either pay for unlimited mode or switch to a fixed-performance instance. M6i instances run at full CPU capacity at all times with no burst mechanism, making them predictable for sustained workloads.
730 hours represents 24/7 uptime across a 30.4-day month. Use this if you are running a production service that must always be available. For a development environment that runs only during business hours, 160 hours (8h × 5d × 4w) is a more realistic figure. Adjusting hours is the quickest way to understand the cost impact of running instances on a schedule.
AWS Graviton (M7g, C7g, R7g, T4g) instances use AWS-designed Arm-based processors and are typically 20% cheaper than their x86 equivalents at similar performance. They are not in this estimator because they require applications to be compiled for Arm architecture, which rules them out for a significant share of legacy workloads. If your stack supports Arm, apply a 0.8 multiplier to the M6i, C6i, or R6i price as a rough Graviton equivalent.
Multiply the per-instance monthly cost by your average number of running instances. For example, if your group scales between two and eight instances with an average of four, use four in the instance count field. If you need to model minimum guaranteed capacity separately from burst capacity, calculate them as two separate estimates.
In order of cost from highest to lowest: on-demand, reserved (1-year no-upfront), reserved (1-year all-upfront), reserved (3-year all-upfront), spot. Spot instances can be up to 90% cheaper than on-demand but can be interrupted with two minutes' notice. They suit batch workloads, stateless web tiers behind an Application Load Balancer, and CI/CD runners that tolerate interruption.