Cloud vs on-premise cost calculator
A structured, honest TCO comparison for steady-state workloads. Every rate is editable. Plug in the numbers from your actual cloud pricing page and your actual hardware quote, because the defaults are ballparks and the vendor whitepapers on both sides are propaganda.
Monthly cost
Cloud
On-premise
Cumulative cost
| Horizon | Cloud | On-premise | Difference |
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How it's calculated. And what it leaves out
Cloud monthly cost is vCPU·rate + RAM·rate + storage·rate + egress·rate, which approximates on-demand instance pricing decomposed into its drivers. On-prem monthly cost is amortized capex (servers × cost / years) plus power at the wall (W × 24 × 365 / 12 × €/kWh. Set your rate to include cooling if you pay it), colocation or rack space, and a support-and-admin percentage that covers vendor contracts, spares and the fraction of a salary that actually runs the thing. That last slider is where most comparisons cheat, in either direction: 0% means your time is free, 40% means you're a bank.
What this deliberately leaves out, on both sides: cloud committed-use and reserved discounts (often 30–60% off. If you'd commit, cut the rates accordingly), spot capacity, licensing deltas (some database licenses price per cloud vCPU brutally), the value of elasticity for spiky workloads (this model assumes steady state, which is exactly where on-prem shines), migration costs, and the opportunity cost of capex. If your workload is spiky or you'd run at 20% utilization on-prem, cloud wins arguments this calculator won't show.
The honest use of this tool: get a real cloud quote and a real hardware quote, put both in, and let the 5-year line settle the meeting. Steady-state infrastructure at decent utilization usually favors on-prem on raw cost. The question is whether the operational load and inflexibility are worth the difference, and that part is your call, not arithmetic.