Bottleneck test. Measured on your machine, not guessed.
Bottleneck calculators estimate from two part names. This test loads your processor and graphics in one run and shows how each one held up.
Plateau, then a single step down.
Throughput held for 18 seconds, then fell in one transition and stayed there. One fall accounts for 98% of everything the run gave up.
Illustrative shape. Your run draws its own, and the report reads that one.
Processor
Every core, 60 s
Graphics
Scene and path tracer
Side by side
One run, one report
Deep run
CPU and GPU together
A calculator guesses. A test measures.
A calculator cannot know your cooling, power limits, drivers or background apps. A measurement on the machine includes all of them.
Both parts, one run
The processor and the graphics are loaded in the same run, on the same machine, minutes apart, so their results can be read side by side.
Held under load
Each part is held at work long enough for power and heat limits to show, which is when a part that looked fine starts to limit the other.
Together on Deep
The Deep run, 9 minutes, adds a stage that loads the processor and graphics at the same time, closer to a game than either stage alone.
Your real setup
Cooling, power settings, drivers and what else is running are all part of the measurement, because they are part of the machine.
What it can say about a bottleneck.
Read the processor and graphics figures together. The report is careful about what one run can establish.
Which part slowed more
The processor's slowdown and the graphics slowdown are shown for the same run, so you can see which one gave up more of its speed under load.
Both slowed together
When both lose speed, the shared cooling or power supply is usually the limit, not one part.
A busy processor
When the Deep run shows the processor faster under combined load than alone, the report says the solo stage was held back, most often by another program.
What it cannot say
It does not predict frame rates in a specific game or at a specific resolution. That depends on the game, and needs an in-game benchmark.
Plateau, then a single step down.
Throughput held for 18 seconds, then fell in one transition and stayed there. One fall accounts for 98% of everything the run gave up.
Illustrative shape. Your run draws its own, and the report reads that one.
Hardware
What it needs. Three tiers, no fine print.
Minimum
Any recent browser
Integrated or dedicated graphics, desktop or laptop.
Recommended
Plugged in, games closed
A game or launcher running in the background changes both results.
Optimal
The Deep run
Adds the combined CPU and GPU stage.
What good looks like
The ranges, before you run it.
Slowdown under long work
- Under 5%
- Holds its speed
- Little lost over the run.
- 5% to 15%
- Normal
- Common on laptops and compact PCs.
- 15% to 30%
- Noticeable
- Long tasks run clearly slower than short ones.
- 30% or more
- Worth checking
- Often heat, dust or a low power limit.
Graphics smoothness
- 90% or more
- Smooth
- Frames arrive at an even pace.
- 75% to 89%
- Mostly smooth
- Occasional uneven frames.
- Below 75%
- Uneven
- Visible stutter is likely in motion.
What a browser cannot see
The honest limits, and where to look instead.
How full your memory is
A web page cannot see how much memory is in use. If the machine slows down with many apps or tabs open, check it directly.
On a Mac: Activity Monitor, Memory tab: Memory Pressure at the bottom. Yellow or red means memory is the limit.
On Windows: Task Manager (Ctrl+Shift+Esc), Performance, Memory. Above about 85% in use while you work means memory is the limit.
Temperatures and fan speed
No browser can read a temperature sensor, so heat shows here only as speed lost over time.
On a Mac: A free app such as Stats shows temperatures and fan speed.
On Windows: HWiNFO, or your laptop maker's own app.
Storage speed and health
Opening apps and files depends on the drive, which this test does not touch.
On a Mac: Disk Utility, then First Aid on your main drive.
On Windows: CrystalDiskInfo shows the drive's health status.
Questions
Bottleneck test, answered
- Are bottleneck calculators accurate?
- Not very. They compare two part names against a table and cannot see your cooling, power limits, drivers or background apps, which are often what actually limits a machine.
- How do I test for a CPU or GPU bottleneck?
- Measure both parts on your own machine under load. This test loads the processor and the graphics in one run and shows how much speed each kept.
- Will it tell me my FPS in a game?
- No. Frame rate in a game depends on that game and its settings. For that, use the game's own benchmark with an on-screen frame rate counter.
- What does it mean if both slow down?
- Usually that the shared cooling or power supply is the limit. On a laptop, the processor and graphics share one heatsink, so heat from one slows the other.
- Is the bottleneck test free?
- Yes. The run and every measured figure in the report are free, with no account and nothing to install.