Keyboard test workspace

Read one press before testing a whole keyboard

Connect a physical keyboard, click a non-interactive area of this page and tap A once. Look for a down event followed by an up event in the recent history. The active highlight should clear on release. Next hold Shift while tapping A, then release both. On a US English layout the produced character changes from a to A, while the physical position remains KEYA. Other input layouts can produce different characters at that same position.

event.key is the reported character or named key; event.code identifies its physical position. The sheet shows the most recent event, including releases, so use the history to follow the sequence. A key can appear in the sheet even when its position is absent from the selected diagram. Changing the diagram does not change your operating-system input layout.

Repeat and stuck are observations, not diagnoses

Hold an ordinary letter briefly to observe automatic repeat, then release it. Repeated down events during a deliberate hold are different from separate taps. The repeat indicator clears on release. This workspace also flags a key still considered held after roughly 1.2 seconds; that heuristic can flag an intentional hold or a missed release event. It is not proof of a mechanically stuck switch.

Reset clears the sheet, history and highlights. Leaving the window also clears the session, so record an observation before switching applications. Copy event copies the last event summary, not a complete hardware report. This workspace cannot measure switch latency, certify a keyboard or detect events intercepted before they reach the page.

If one key does not respond

1. No ordinary letters respond: confirm the page has focus and scripts are enabled. Try an ordinary letter again before investigating an individual key. A phone touch keyboard is not an equivalent physical-key test.
2. The key works elsewhere: return focus here, check the active layout and compare another browser. System shortcuts, Fn and some media controls may never produce a page event. A modifier need not insert text in an editor, so test its intended behavior rather than expecting a printed character.
3. It works alone but fails in a combination: note the smallest failing group and press order, then use the rollover test. One failed combination does not identify a broken switch.
4. The same ordinary key fails across applications: check the connection or battery, then compare another keyboard on this computer or this keyboard on another computer. Change one variable at a time. Follow the manufacturer’s model-specific service instructions; browser results do not justify removing a keycap or reseating a switch.

Keep the keyboard model, connection, operating system, browser, active layout, key or combination and observed down/up sequence together. See the full missing-key procedure for deciding what to check next.

Choose the view for your question

This workspace is for the event sequence: key, code, location, modifiers, repeat and the held-state warning. Use Keyboard Key Test for per-key counts that exclude automatic repeat, or Full Keyboard Test to work through tested and untested diagram positions. None of these views certifies every simultaneous combination; use a recorded combination in the rollover tool for that narrower observation.

Reference: MDN physical key codes and automatic repeat events. See our measurement methods and limits.