Run quick browser checks for keyboard input, mouse clicks, microphone level, and display pixels. Choose a test; nothing is installed.
Press keys to check each key. Hold several keys together to see which simultaneous key presses your browser reports.
Click the on-screen keys you plan to hold, then press that combination on your keyboard. Highlighted keys show what the browser received.
A missing key in a selected combination can suggest key blocking. Browser shortcuts and operating-system handling can also hide key events.
Key rollover check: This records simultaneous keydown events the browser receives. It can reveal missed combinations in this test, but it cannot certify the keyboard’s maximum N-key rollover or detect every form of ghosting.
TECHNICAL PARAMETERS / Browser-based key combination monitor: Counts simultaneous keydown events received by this page and compares the keys you selected with the keys observed. Browser shortcuts and operating-system handling can intercept keys. This check cannot certify full N-key rollover (NKRO) at the keyboard hardware or firmware level.
One row per key press. Repeats and keys outside your selected combination are marked.
| Time | Key | Event | Status |
|---|---|---|---|
| Press a key to start the log. | |||
Click the target repeatedly. Adjust the rapid-pair interval and inspect left-button presses under 80 ms apart for an unusual repeat pattern.
Counts left-button presses less than 80 ms apart on this target. This can help reproduce a double-click symptom; it cannot identify a faulty switch or measure hardware debounce.
Last press gap:Move your mouse steadily for two seconds. The browser counts raw or coalesced pointer samples when available and notes delivery gaps. This does not measure USB polling or hardware latency.
If your browser exposes a compatible HID report stream, select the device and observe reports during a two-second sample. Move the device or press keys while sampling.
No HID device connected.
Browsers normally block generic mouse and keyboard HID reports. A visible report stream may be for an auxiliary interface and does not prove an 8000 Hz USB polling rate.
TECHNICAL PARAMETERS / High-speed pointer sample estimator: Counts pointer samples delivered to this page during a two-second movement test, including coalesced samples when the browser exposes them. Rapid-repeat clicks are counted separately. Optional WebHID counts reports only from a compatible device interface that the browser permits. None of these readings certifies an exact 8000 Hz USB polling rate or hardware latency.
Start the check and allow microphone access. Live signal analysis runs in your browser. Recording and playback are optional and start only when you choose Record.
Microphone is off
Frequency bands describe the signal delivered by your microphone and browser. They are not a calibrated microphone response test.
References: AnalyserNode API · MediaRecorder API
Use speakers (not headphones). Keep the microphone close to one speaker in a quiet room, then play three short reference tones.
Start the microphone first, then run this check.
This is a relative browser estimate, not an absolute wiring certification. Speaker polarity, acoustic reflections, echo cancellation, and noise processing can affect the result.
One local reading per second. The log keeps the latest 120 readings.
| Time | Level | RMS level | Peak level | Strongest detected tone | Bass · 20–250 Hz | Mids · 250 Hz–4 kHz | Treble · 4–20 kHz | Clipped samples |
|---|---|---|---|---|---|---|---|---|
| Start the microphone to collect readings. | ||||||||
Audio analysis and optional recording stay in this browser. Recording begins only when you choose it; nothing is uploaded.
Inspect full-screen solid colors, near-black, and gray, or start a slow automatic cycle. These views can reveal visible pixel faults and unevenness on OLED and IPS panels.
This visual check cannot diagnose or repair a display. Clean the screen and inspect it at comfortable brightness. Image retention and permanent burn-in are different conditions.
Use the slow color cycle, gray, and near-black views to look for visible pixel faults or unevenness on OLED, Tandem OLED, and IPS screens. This visual test cannot identify the panel type or confirm permanent burn-in.
TECHNICAL PARAMETERS / Pixel fault & uniformity checker: Shows full-screen solid colors, gray, and near-black for your own visual inspection of stuck pixels and unevenness. It cannot identify the panel type or diagnose permanent OLED burn-in or hardware degradation.
Keyboard and pointer events stay in this page. WebHID asks permission only if you choose a device; reports are counted locally. Microphone analysis starts after permission and stays here; audio is recorded only if you choose the optional recorder.
Run quick browser checks for keyboard input, mouse clicks, microphone level, and display pixels. Choose a test; nothing is installed. The keyboard view lights up browser-reported keys and counts simultaneous presses. The mouse test counts clicks and rapid pairs; its pointer-rate number is an estimate of events delivered while you move the cursor. The microphone view shows a live input level after you grant browser permission. The screen view fills the display with solid colors for a visual pixel check.
Select the keyboard tab and press keys one at a time to see them light up. Then hold a few keys together and check the simultaneous count. The timestamped event log records keydown and keyup events, flags browser repeat events, and marks keys outside a selected combination. Keyboard matrix design, operating system handling, and the browser affect what is reported. This online mechanical keyboard test is a practical input check, not a certified N-key rollover measurement or a guarantee that every key combination is ghost-free.
Use the mouse target at your regular clicking speed. The tool counts two clicks within the selected interval as a rapid pair. For the polling-rate estimate, move the pointer steadily during the timed sample. Browsers may combine or delay pointer events, so the observed rate can differ from the hardware polling rate shown by a device utility.
Open the screen test and switch through red, green, blue, white, black, and gray. A stuck or dark pixel may stand out against some colors. On OLED phones, gray and white screens can help reveal uneven aging or temporary image retention. Keep brightness comfortable and close the overlay to return to the page.
The tester asks for microphone permission only after you start it. It analyzes RMS level, peak, clipping, the strongest detected tone, and relative bass, mid, and treble bands in the browser. It adds one measurement to a local log each second; download the latest 120 readings as CSV. Recording is optional and limited to 15 seconds, with playback and download on this page. Neither the measurements nor recording are uploaded.
The page reads browser keydown, pointer, and optional WebHID inputreport events. Browser pointer events may be combined or delayed, and Chrome blocks generic keyboard and mouse HID report collections. Results describe what this browser received during the test, not a laboratory measurement of the device.
Open BFOTKit.com and choose the mouse test. Click the target at your usual speed to see whether rapid pairs are being registered. This can confirm the symptom, but switch wear, settings, or software may still need separate diagnosis.
Open BFOTKit.com and choose the keyboard test. Press keys together and review the simultaneous events the browser reports. Ghosting or key blocking depends on the keyboard matrix and tested key combination; this browser check does not certify the hardware’s full rollover limit.
Open BFOTKit.com and use the mouse event-rate check or optional WebHID report check. Browser pointer samples and accessible HID input reports are useful observations, but standard mouse reports are protected and neither number certifies an 8000 Hz USB polling rate. Use the manufacturer’s device utility for its configured rate.
Open BFOTKit.com and click the mouse target to inspect rapid pairs and left-button presses under 80 ms apart. Repeated very fast presses can reproduce a symptom, but the browser cannot prove whether the switch, firmware, settings, or software caused it.
Open BFOTKit.com and choose the screen test. Use the color controls to inspect the full viewport; rotate your phone if helpful and close the test when done. It does not repair pixels or prove that an OLED panel has permanent burn-in.
Open BFOTKit.com and choose the microphone test. Live levels and frequency bands are analyzed in your browser. Recording is optional: select Record, then play or download the captured sample in this page. The recording stays in browser memory and is not uploaded.