How Our Bottleneck Calculator Works
A bottleneck calculator is only useful if you know what its result actually means — and what it does not mean. This page explains, in plain language, what our calculator compares, which factors shape its estimate, how to read the balance bands it reports, and where its honest limits lie.
We would rather you understood the method and used the result wisely than treated a single percentage as a verdict on your PC. Read this page alongside the calculator itself, and you will get far more from both: a sensible sense of where your system stands, and a clearer idea of what, if anything, is worth changing.
What the calculator compares
At its core, the calculator compares the relative gaming capability of your processor and your graphics card. Those two components do different jobs in every frame: the processor prepares the frame, handling game logic, draw calls and simulation, and the graphics card renders the image you see. If one is substantially weaker than the other for a given workload, it limits the stronger one.
The calculator expresses that relationship as an estimated balance figure. It is a comparison between two components in a stated context, not a measurement taken from your machine. Your PC is not benchmarked, nothing is installed, and no data is read from your hardware; the estimate is worked out from the components and settings you select, using the performance data and factors described below.
The factors in the estimate
Component performance data
Each processor and graphics card carries a relative performance profile drawn from its specifications and widely reported gaming behaviour. Comparing those profiles is the starting point for the estimate.
Resolution
Resolution changes the balance substantially. At 1080p the processor does a larger share of the limiting, while at 1440p and 4K the graphics card takes on far more of the work, so the same pairing can read differently at each setting.
Refresh target
A 60Hz monitor and a 240Hz monitor ask very different things of a system. Aiming for higher frame rates raises the demand on the processor in particular, which is why your target matters to the result.
RAM
Memory capacity, speed and channel configuration can all affect frame delivery. Too little memory, or a single-channel setup, can hold a system back even when the processor and graphics card are well matched.
Workload profile
Games differ. A large open-world title, a competitive shooter and a heavy simulation load components in different proportions, so the estimate takes the type of workload into account rather than assuming all games behave alike.
For context on which components players actually use, the Steam Hardware Survey publishes a useful public snapshot of hardware popularity across a very large number of gaming PCs, and we refer to it as background context rather than as a performance source.
How to read your result
Read the balance figure as a band, not as a precise score. As a guide, a result under 10 per cent suggests a generally balanced pairing for the settings you chose, where neither component is holding the other back in an important way. A result between 10 and 20 per cent suggests a minor imbalance: you may notice it in some games or at some settings, but it is rarely a reason on its own to replace a component.
A result over 20 per cent suggests a significant imbalance, where one component is likely limiting the other often enough to be worth attention — particularly if you are already planning an upgrade. Even then, treat the band as guidance. A system can show a notable imbalance on paper and still play the games you enjoy perfectly well at your settings, in which case there is no practical problem to solve.
What the calculator cannot do
The calculator cannot measure your actual frame rates, and its result is not a guaranteed FPS measurement. Real performance varies with the individual game and how well it is optimised, the graphics settings and driver version in use, background software, storage speed, and how effectively your cooling lets components sustain their speeds over a long session.
It also cannot see your specific unit, its condition, or any overclock or power limit applied to it. For those reasons, we recommend confirming any spending decision with monitoring on your own system, in your own games, before you buy. If your measured experience and the estimate disagree, trust the measurement taken from your PC.
How we keep it current
Component line-ups change quickly, so the underlying profiles are reviewed as new processors and graphics cards are released and as driver and game updates shift real-world behaviour. When a new generation arrives, its relative standing is assessed against the existing catalogue so that comparisons across generations remain consistent.
We also revisit the way factors such as resolution and workload are weighted when the evidence warrants it, and we correct errors when readers report them. If a result for your system looks plainly wrong, telling us which components and settings you selected helps us investigate far more than a general note that a figure seemed surprising.
Frequently asked questions
Is a bottleneck percentage a measurement of my PC?
No. It is an estimate based on the components and settings you select and on their relative performance profiles. Nothing is read from or installed on your machine, so use it for planning and comparison rather than as a diagnosis.
Why does my result change when I change the resolution?
Because resolution redistributes the work. Lower resolutions place relatively more weight on the processor, while higher resolutions load the graphics card far more heavily, so the balance between the same two components shifts with the setting.
Should I upgrade if my result is over 20 per cent?
Not automatically. A significant imbalance means one component is likely limiting the other in many situations, but if your games already run as you want at your settings, there is nothing you need to fix. Upgrade when the limit affects your experience, not merely because a band says it exists.
Why might my real FPS differ from what I expected?
Many things influence real frame rates besides component balance, including game optimisation, settings, drivers, cooling, background tasks and memory configuration. The calculator accounts for some of these as factors, but it cannot replicate your exact system and software state.
Continue checking your build
Return to the homepage and main bottleneck calculator, follow the practical walkthrough in how to use our bottleneck calculator, and run the dedicated CPU bottleneck calculator, GPU bottleneck calculator and FPS calculator for each side of your system.
Calculator results are estimates for planning, not measurements or guarantees. Actual results depend on the game, resolution, settings, drivers, cooling and what else is running on the PC.