PSU Wattage Calculator

Add up your GPU, CPU and everything else, then size a power supply with real headroom — not one that just barely covers today's build. Enter your own components' rated wattage below.

PSU Wattage Calculator

Enter your own components' rated wattage (from the box or spec sheet) — this doesn't assume any specific product's power draw.

375W

total system draw

550W

recommended PSU tier

Based on your 375W total plus a 30% headroom margin (≈488W) — headroom protects against power spikes and leaves room for future upgrades, not just today's build.

See real 550W-class power supplies with honest buying criteria.

Read the PSU Buying Guide

Estimate only — always check your GPU manufacturer's minimum PSU recommendation too

Why headroom matters

Modern GPUs can have brief power spikes well above their average draw, and a PSU running near its max capacity constantly runs hotter and less efficiently. Full buying criteria — efficiency ratings, connector types, modular vs. non-modular — are in our PSU buying guide.