The test records the precise timestamp of every keydown event using JavaScript's performance.now() API, which provides sub-millisecond timing. By measuring the gaps (intervals) between consecutive keydown events and computing their average, it derives how many times per second your keyboard is reporting input — which is its polling rate in Hz. Statistical analysis including standard deviation identifies jitter in your keyboard's polling consistency.

Several factors can cause lower-than-rated results: (1) OS scheduling jitter adds overhead to event delivery, (2) the browser introduces additional latency between hardware events and JavaScript callbacks, (3) USB hubs and extension cables add latency, and (4) insufficient keystroke samples reduce statistical accuracy. For the most accurate result, hold a key continuously for the full 10 seconds and ensure your keyboard is plugged directly into the motherboard USB port.

1000Hz (1ms interval) is the gold standard for competitive gaming keyboards and is used by the vast majority of professional esports players. The 8000Hz polling rate offered by keyboards like the Wooting 60HE+ and Razer Huntsman V3 Pro reduces latency to 0.125ms, which is theoretically beneficial but indistinguishable for most players. For office use and non-competitive gaming, 125Hz is perfectly adequate.

A minimum of 20 samples (keystrokes) is needed for a low-confidence estimate, 50+ samples for medium confidence, and 100+ samples for high confidence. The test automatically classifies confidence based on sample count. For the most accurate result, hold a key for the full 10-second test duration which will collect 1000+ samples at 1000Hz polling rate.

Jitter in the keyboard polling rate test is the standard deviation (σ) of interval measurements in milliseconds. A lower jitter value means your keyboard is delivering events very consistently — desirable for gaming. A high jitter value (>0.5ms) suggests unstable polling, possibly due to USB bandwidth issues, faulty cable, or interference. Gaming-grade keyboards typically show jitter below 0.3ms.

Browser-based testing has limitations at 8000Hz (0.125ms interval). Most browsers cannot resolve individual events at this speed due to their event loop architecture, so 8000Hz keyboards will typically test at 1000–4000Hz in a browser environment. For definitive 8000Hz verification, use the manufacturer's official software (Wooting app, Razer Synapse) which accesses hardware directly.

Yes. Built-in laptop keyboards are typically fixed at 125Hz (8ms interval) through their embedded PS/2 or I²C controller and cannot be changed via software. This is why laptop keyboards test at approximately 125Hz regardless of what games or software you use. For gaming on a laptop, connect an external USB gaming keyboard which will operate at its rated polling rate (usually 1000Hz).

The formula is: Hz = 1000 ÷ interval_in_ms. So a 1ms interval equals 1000Hz, a 2ms interval equals 500Hz, and an 8ms interval equals 125Hz. Conversely, to find the interval from Hz: ms = 1000 ÷ Hz. This calculator handles both conversions automatically and also shows the comparison across all standard polling rate tiers.

1000Hz became the gaming standard because it provides a 1ms polling interval, which is far below the threshold of human perception (~5ms) and well under average human reaction time (150–250ms). It also aligns with common gaming monitor refresh rates of 144Hz–240Hz. At 1000Hz, the keyboard delivers enough input resolution that polling rate is no longer the bottleneck in competitive gaming.

1000Hz is the recommended keyboard polling rate for CS2 and Valorant. Professional players universally use 1000Hz keyboards. While 8000Hz keyboards like the Wooting 60HE+ are popular among pro players for their analog input features, the polling rate advantage over 1000Hz is negligible in practice. Focus on switch quality, actuation force, and key travel consistency rather than polling rate.

8000Hz keyboards generate 8 times more USB interrupt requests than 1000Hz keyboards. On modern CPUs this is negligible — the extra CPU load is measured in fractions of a percent. However, on older systems (pre-2015 CPUs) or with many high-polling devices connected simultaneously, 8000Hz can cause slightly higher CPU interrupt overhead. 1000Hz has zero measurable impact on any modern system.

In blind testing, the vast majority of players — including professionals — cannot distinguish 1000Hz from 8000Hz keyboard polling rate in gameplay. The 0.875ms difference (1ms vs 0.125ms) is imperceptible. 8000Hz keyboards are still valuable for their other features like rapid trigger (which detects key release points at sub-millimeter precision) rather than the polling rate itself.

Laptop keyboards connect to the motherboard via an embedded PS/2-compatible or I²C controller with a fixed 125Hz polling rate built into the firmware. Unlike USB peripherals, this cannot be changed through software or drivers — the hardware itself limits the rate. The only workaround is to use an external USB gaming keyboard, which will operate at its rated 1000Hz+ polling rate regardless of being on a laptop.

Polling rate is how often the keyboard sends data to your PC, measured in Hz. Response time is how quickly a switch actuates and registers after being pressed, measured in milliseconds. They are different latency sources. A 1000Hz keyboard sends data every 1ms. A typical mechanical switch has a response time (travel + bounce time) of 5–15ms. Both contribute to total input latency, but switch response time usually dominates.

"key" represents the logical character the key produces (e.g., "a", "A", "Enter") and changes with modifier keys and language layout. "code" represents the physical location of the key on the keyboard regardless of layout (e.g., "KeyA", "ShiftLeft") and never changes. "keyCode" is a deprecated numeric code from older browsers (e.g., 65 for A). For modern development, always use "key" for characters and "code" for physical key detection.

The repeat flag is true when a keydown event is being fired repeatedly because the key is being held down and the OS key-repeat function is generating additional events. Most keyboards start repeating after an initial delay (~500ms) and then fire at ~30Hz. Repeat events have the same key/code values as the original keydown but can be filtered out using "if (event.repeat) return;" for games that only need the initial keypress.

Use the event stream to look for: (1) Missing keyup events — indicates sticky keys or switch bounce; (2) Unexpected keyCode values — indicates key remapping or a different keyboard layout than expected; (3) Hold time inconsistencies — very short hold times may indicate switch chatter (double-firing); (4) Double keydown events without keyup — indicates switch debounce failure common in faulty mechanical switches.

For a brief tap, keyboard hold duration (the time between keydown and keyup) is typically 50–150ms for normal typing. Gamers making quick inputs may achieve 30–60ms hold times. Hold durations below 10ms may trigger switch chatter/bounce detection in some keyboards. The hold time shown in the inspector reflects actual physical key press duration including any switch debounce time.

The "keyCode" property (now deprecated) was designed around the US QWERTY layout and returns layout-independent codes for most keys, but varies for special characters. For example, the ";" key returns keyCode 186 on US QWERTY but different values on French AZERTY or German QWERTZ layouts. This is why modern applications use "code" (physical key location) for shortcuts and "key" (actual character) for text input.

The inspector cannot directly identify switch type, but you can infer it through timing. Optical switches (e.g., Razer Optical, Gateron IR) typically show near-zero debounce time and very consistent response times because there is no physical contact bounce. Mechanical contact switches may show slight variation. Extremely short and consistent intervals between keydown and the first repeat event can suggest an optical switch.

Yes. The inspector captures all standard keyboard events including macro keys, media keys, and function keys. However, some macro keys that are handled entirely by the keyboard hardware or its driver software may not send standard keydown/keyup events to the browser. Media control keys (Play, Pause, Volume) send events with special key values like "MediaPlayPause" and "AudioVolumeUp" which will appear in the stream.

Keyboard ghosting occurs when you press multiple keys simultaneously and one or more keypresses go unregistered — or a phantom "ghost" key appears that was never pressed. This happens because standard keyboard matrix circuits cannot always distinguish all combinations of simultaneous keys. In fast-paced games like FPS shooters where you might hold WASD + Shift + Space simultaneously, ghosting can cause you to stop moving unexpectedly or miss critical inputs during combat.

6KRO (6-Key Rollover) means the keyboard can accurately register up to 6 simultaneous keypresses — the USB HID standard limit. Most gaming keyboards offer 6KRO which is sufficient for the vast majority of games. NKRO (N-Key Rollover) means every single key has its own electrical pathway and can be pressed simultaneously with all other keys without any ghosting or blocking. NKRO typically requires a PS/2 connection or a gaming keyboard with special USB NKRO firmware.

No. While marketing often implies it, many mechanical keyboards only offer 6KRO over USB. True NKRO is found on premium gaming keyboards like the Ducky One, Leopold FC900R, and Corsair K70. Some keyboards offer NKRO only when connected via PS/2 adapter. Use this ghosting test to verify actual rollover performance of your specific keyboard rather than relying on marketing claims.

Press and hold keys that you would normally use simultaneously in games — for example, hold W+A+Space+Shift+Ctrl (sprint-jump-strafe). Watch the visual keyboard layout and the "Keys Held" counter. If the counter stops incrementing or shows fewer keys than you are physically holding, your keyboard is ghosting or blocking those keys. The "Rollover Type" badge will update to show the maximum simultaneous keys your keyboard supports.

The most common ghosting zones are around the WASD cluster when combined with Shift, Ctrl, Space, and nearby letter keys. Specifically: W+A+D with Shift or Ctrl is a notorious ghosting combination on budget keyboards. The number row with modifier keys also frequently ghosts. Diagonal movement (W+A or W+D) combined with any third key is where most gaming keyboards first show their rollover limits.

No, and this is a common marketing confusion. "Anti-ghosting" typically means the manufacturer has optimized the key matrix to prevent phantom (ghost) keystrokes from appearing — but does not guarantee full simultaneous key registration. N-Key Rollover (NKRO) is the stronger specification that guarantees every key registers independently. A keyboard can be "anti-ghosting" (no phantom keys) while still blocking certain simultaneous combinations.

Yes — browsers receive keydown and keyup events for every key the keyboard reports to the OS. If your keyboard supports NKRO and the OS is correctly receiving all simultaneous key inputs, the browser will receive and display all of them. The only limitation is that some browser keyboard shortcuts (like Ctrl+W which closes a tab) may interfere with testing those specific key combinations. For those keys, test in a dedicated keyboard testing application.