A CPU’s rated TDP is a useful reference number, but it is not the same thing as what the chip actually pulls from the wall while you use your PC. This calculator estimates real-world power draw at idle, typical everyday use, and full sustained load, helping you plan a power supply, estimate electricity cost, or understand why your CPU runs hotter or cooler than its spec sheet number alone would suggest.
| CPU | Rated TDP | Idle | Gaming | Full load |
|---|---|---|---|---|
| Ryzen 5 5600 | 65W | 10W | 48W | 88W |
| Ryzen 5 7600 | 65W | 10W | 48W | 88W |
| Ryzen 7 7800X3D | 120W | 18W | 73W | 162W |
| Ryzen 7 9800X3D | 120W | 18W | 73W | 162W |
| Core i5-13400F | 65W | 10W | 81W | 148W |
| Core i5-14600K | 125W | 19W | 100W | 181W |
| Core i9-14900K | 125W | 19W | 139W | 253W |
Idle is about 15% of TDP, gaming about 55% of the max turbo/boost power (45% for X3D chips), full load the maker’s max power spec.
How this is calculated: the formula on our Methodology page. Sources: part specs from each maker’s official product page (our hardware database); Intel “Maximum Turbo Power” and AMD PPT specs.
Quick answer
This calculator estimates a CPU’s real-world power draw at idle, typical use, and full sustained load using its rated TDP for idle (about 15%), about 55% of the manufacturer’s maximum turbo/boost power for gaming or everyday use (45% for AMD X3D chips), and that maximum power for full load, since unlocked chips can draw far more than their TDP in sustained heavy work (the Core i9-13900K: 125W TDP, 253W maximum turbo power). It’s meant for sizing a power supply or estimating running cost, not as a wattmeter reading.
How Many Watts Does a CPU Use?
It depends on the chip and the work. By the calculator’s estimates, a Ryzen 5 7600 (65W TDP) uses about 10W at idle, 48W while gaming and 88W at full load. A Ryzen 7 7800X3D uses about 73W in games and 162W at full load. A Core i9-14900K, also sold as a 125W TDP chip, uses about 19W at idle, 139W in games and up to 253W at full load. So the TDP on the box is a cooling figure, not the wattage: high-end unlocked chips can draw about twice their TDP in long all-core work.
The CPU is one part of the total. For the whole PC’s wattage and electricity cost, use the PC Power Consumption Calculator; for the power supply size, the PSU Calculator.
What the Result Means
The calculator returns estimated power draw figures in watts for different usage levels, rather than a single number. Idle power draw reflects what the CPU pulls when the system is on but mostly waiting for input — light browsing, sitting at the desktop. Typical load reflects common everyday tasks like general productivity work or lightly-threaded gaming. Full load reflects sustained heavy multi-core work, such as video rendering or running a demanding benchmark for an extended period, where the CPU is using as much of its available power budget as its cooling and motherboard allow.
These figures matter most for two practical decisions: sizing a power supply with adequate headroom, and estimating how much a CPU actually contributes to your electricity bill or to your case’s total heat output during real usage rather than worst-case usage.
How This Calculator Works
The calculator uses two manufacturer figures. Idle is scaled from the CPU’s rated TDP: about 15%, because most cores drop to low-power states. Gaming and everyday use take about 55% of the manufacturer’s maximum turbo/boost power (Intel’s Maximum Turbo Power, or AMD’s package power limit, PPT), or 45% for AMD X3D chips, whose extra cache keeps clocks and power lower; that tracks review measurements better than the TDP, which over-states X3D chips and under-states unlocked Intel K chips. Full load uses the maximum turbo/boost power itself, because many boards let a CPU hold that limit through long all-core work, well above its TDP.
As a worked example, take the Intel Core i5-13600K, rated at 125W TDP with 14 cores and 20 threads. The calculator puts it at about 19W at idle (15% of 125W) and about 100W in gaming or everyday use (55% of its 181W Maximum Turbo Power). Under sustained full multi-core load, such as a long video export, it uses Intel’s 181W Maximum Turbo Power, well above the 125W TDP, because most boards let the chip hold that limit.
Compare that to the AMD Ryzen 5 7600 (65W TDP): about 10W at idle, 48W in gaming and 88W at full load (its PPT), roughly half the i5-13600K’s full-load figure. That is why the calculator reads each CPU’s own figures rather than using one flat number for every chip.
Important Limitations
These figures are estimates derived from rated TDP, maximum turbo/boost power and typical scaling behavior, not measurements taken from a physical wattmeter on your exact motherboard and cooling setup. Actual power draw is affected by motherboard power limit settings (some boards allow a CPU to exceed its rated TDP for extended periods, sometimes called “unlocked” or “performance” power profiles), cooling quality (better cooling can allow sustained higher power draw before thermal throttling kicks in), and the specific software workload running at the time.
This calculator also does not measure your full system’s power draw — it estimates only the CPU’s contribution. For total system power planning, including your GPU and other components, use the PC Power Consumption Calculator. Treat these numbers as reasonable planning estimates, not as a substitute for an actual power meter reading.
Frequently Asked Questions
Is TDP the same as actual power consumption?
Not exactly. TDP is primarily a thermal design specification used to guide cooling requirements, and it happens to correlate reasonably well with power draw under heavy sustained load, but idle and typical-use power draw are usually well below the TDP figure.
Can a CPU actually draw more power than its rated TDP?
Yes, on many modern desktop CPUs, especially when a motherboard is configured to allow extended boost duration or a raised power limit. This is common on unlocked “K” or “X” series chips left at motherboard default settings rather than strict TDP-limited settings.
Does a higher core count always mean higher power draw?
Generally yes at full load, since more cores working simultaneously draw more total power. At idle, however, core count matters much less, because idle cores drop into low-power states regardless of how many total cores the chip has.
How does CPU power draw affect my power supply sizing?
Your CPU’s peak power draw is one part of your total system load, alongside your GPU and other components. Sizing a power supply around only typical-use power draw instead of peak load risks instability during demanding, sustained workloads.