PSU Calculator
Estimate your system load and a sensible power supply wattage with configurable headroom.
This is an estimate based on your inputs; check your component requirements before buying.
What this tool does
The PSU estimate combines approximate CPU, GPU and component power with a reserve margin. Use it as a shortlist starting point, not as a guarantee: transient GPU spikes, connector requirements, PSU quality and manufacturer recommendations matter when selecting a unit.
How to use it
Enter the values requested by the calculator and check the result together with the notes shown below it.
Practical example
Use a realistic example from your own setup to compare scenarios. The result is a reference, not a replacement for manufacturer specifications.
How to interpret the result
Treat the result as an estimate whenever real-world factors are not available to the browser. For hardware, network or safety decisions, verify the relevant technical specifications.
Frequently asked questions
How much headroom should I leave on the PSU?
A margin of 20–30 % over the estimated draw is usually recommended, to absorb load spikes and let the PSU work comfortably.
Does the 80 PLUS rating matter?
It indicates efficiency: a higher rating wastes less energy as heat, but it does not increase the available power.