Tests
Every free test, in one place.
The stress test for the computer itself, the stage benchmarks behind it, and the device lab for everything around it. All in the browser, nothing to install.
The index
Pick a test. See what it takes first.
The stress test
Is the computer slow, and why? Every page here starts the same run.
- Run the stress testStart hereEvery stage, or 9 minutes Deep.Answers: CPU, memory, GPU and path tracing under sustained load, and why it slows downTakes 3 minAsks for NothingRun test
- PC performance testOnline, free, measured on your machine.Answers: The whole machine under load: processor, memory and graphics, and what it keepsTakes 3 minAsks for NothingRun test
- CPU stress testEvery core, held under load.Answers: Sustained throughput on every core, the slowdown and its shapeTakes 3 minAsks for NothingRun test
- CPU benchmarkHow fast your processor is, measured.Answers: How fast the processor is: peak and sustained M ops/s on every coreTakes 3 minAsks for NothingRun test
- GPU stress testThe same scene on every card.Answers: Frame rate, pacing and slowdown on a fixed scene, then path tracingTakes 3 minAsks for NothingRun test
- RAM speed testBandwidth and latency, measured.Answers: Memory bandwidth from one thread and all, cache and memory latencyTakes 3 minAsks for NothingRun test
- Laptop stress testDoes it hold its speed?Answers: Whether a laptop holds its speed, and power limit against heatTakes 3 minAsks for NothingRun test
- Mac benchmarkIn Safari, nothing to download.Answers: The same run on Apple silicon and Intel Macs, in Safari or ChromeTakes 3 minAsks for NothingRun test
- Bottleneck testMeasured on your machine, not guessed.Answers: Processor and graphics slowdown, measured side by sideTakes 3 minAsks for NothingRun test
Stage benchmarks
How each stage is measured, on its own page.
- Path tracingContinuous GPU load.Answers: Samples per second and how evenly they are delivered, at a fixed 960 by 540Takes In the runAsks for NothingOpen
- GPU rasterA fixed scene.Answers: Frame rate, pacing and slowdown at a fixed 1600 by 900Takes In the runAsks for NothingOpen
- Soft shadowsRuns on its own page.Answers: What real-time PCSS costs your card against hard shadowsTakes 60 sAsks for NothingRun test
- RecoveryRuns on its own page.Answers: Whether the processor comes back at its warm speed after 45 seconds idle, and how fast it settlesTakes 75 sAsks for NothingRun test
- StorageRuns on its own page.Answers: Sequential write and read in MB/s and random 4 KiB IOPS through the browser's private file store, medians across passesTakes Half a minuteAsks for NothingRun test
- ResponsivenessRuns on its own page.Answers: Main-thread delay, input to paint and missed frames with every core but one loaded for 30 s, each against idleTakes 40 sAsks for NothingRun test
- WebGPU computeRuns on its own page.Answers: A compute shader's GFLOP/s with the count stated, the median of one-second windows, dispatches per second, and a 64 MiB copy in GB/sTakes Half a minuteAsks for NothingRun test
- GPU artefact testRuns on its own page.Answers: Integer hash chains against a known checksum, graphics memory written with three patterns and verified, and a fixed scene compared with its first frameTakes 30 s compute, then memory and framesAsks for NothingRun test
- CPU stabilityRuns on its own page.Answers: An integer checksum, a floating-point sum and a Lucas-Lehmer prime test on every logical core, each answer checked against one known in advanceTakes 5 min, or 60 s quickAsks for NothingRun test
- MethodologyEvery figure, and every limit, stated.Answers: How each stage measures, how the grade is computed, the corrections policyTakes A readAsks for NothingRead
Device lab
Everything around the computer, each with a verdict and a fix.
- All device testsFifty-five single tests and eight sets.Answers: Webcam, microphone, speakers, keyboard, mouse, controller, touch, pen, phone sensors, pixels, backlight bleed, refresh rate, frame pacing, headphones, internet, batteryTakes Seconds eachAsks for Per testOpen the lab
- Monitor motion testRefresh, pacing, skipping, ghosting, blur.Answers: The refresh rate with the cause if it is low, frame pacing scored, frame skipping, the overdrive step from what you see, the blur your rate makesTakes 30 s compute, then memory and framesAsks for NothingRun the test
- Browser graphics checkHardware acceleration, WebGL and WebGPU.Answers: Whether the browser draws on the graphics chip or in software, the renderer it names, and the fix for your browserTakes InstantAsks for NothingRun the check
- Video decode testAV1, HEVC, VP9, H.264.Answers: Which decoder the browser claims for each codec at 1080p and 4K, and the decode speed measured on a clip made on the pageTakes Under a minuteAsks for NothingRun the test
- VRAM testErrors counted, bandwidth measured.Answers: Graphics memory written with three patterns and read back, grown to a cap you choose, and copy bandwidth in GB/sTakes Up to a minuteAsks for NothingRun the test
- USB drive speed testAnd fake capacity.Answers: Write and read speed on a drive you pick, every byte read back and checked, with an optional full checkTakes Minutes to hoursAsks for A folder on the drive, Chrome or EdgeRun the test
- Controller polling testReport interval, not input lag.Answers: How often controller data reaches the browser through the Gamepad API, and the controller's own reports over WebHID in ChromeTakes 5 s a readingAsks for A button pressRun the test
- Reaction time testWith what your setup adds.Answers: Your median in ms, and the screen's and mouse's share, measured on the page and taken out as a rangeTakes Five trialsAsks for NothingRun the test
- Bufferbloat and jitterPing with the line busy.Answers: Latency idle and while downloading and uploading, graded on Waveform's bands, and RFC 3550 jitterTakes 12 sAsks for NothingRun the test
- System compatibility checkThe packaged check, in one run.Answers: What an exam or call platform checks before it lets you inTakes 5 minAsks for Camera, Microphone, Screen share, LocationRun check
Questions
Which test, answered
- Which test should I run?
- For "is my PC slow, and why", run the stress test: 3 minutes, every stage. The CPU, GPU, RAM, laptop, Mac and bottleneck pages start the same run and explain the part of the report that answers that question. For a camera, microphone, keyboard, screen or connection, use the device lab.
- Are all of these free?
- Yes. Every test and every measured number is free, with no account and nothing to install. A one-time payment unlocks the stress test's diagnosis section, which names the likely cause of a slowdown.
- Do the tests run in any browser?
- Chrome, Edge, Firefox and Safari on a laptop or desktop. The GPU stages need WebGL2, which every current browser has. A few device checks need a permission the browser asks for.