Track mouse position live
Live mouse coordinates across page, viewport, and a tracking area — plus button state and velocity. Runs entirely in your browser.
How mouse tracking works
Browsers expose pageX/Y and clientX/Y on every mouse event. Page coordinates ignore scroll; client coordinates are viewport-relative.
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Move the mouse
Each pixel of motion updates all four coordinate spaces.
Inputs are treated as UTF-8 throughout the pipeline and validated client-side as you type — nothing dispatches until the value is well-formed.
moveinpututf-8client-sidevalidatedinput · textmousemove · setpageX, pageY
loaded · parsedclient-side - 02
Click buttons
Five-button mice supported — left/right/middle/back/forward.
Each toggle re-computes through a memoised hook, so flipping options never resets your input and the UI stays snappy on large inputs.
buttonsoptionslivememoisedtogglesbuttons · memoisedbitmask · livepressed
options set · memoisedlive - 03
Watch velocity
Computed from dt + distance between mousemove events.
Randomness — where used — comes from
crypto.getRandomValues, neverMath.random. Heavy work sits inuseMemo.velocitycomputeinstantlocaldeterministicv · instantpx/s · computed1240 px/s
computed · instantinstant - 04
Use coords
Read these values for drag, tooltips, custom cursors.
Copy writes through
navigator.clipboardand downloads use aBlob— zero network traffic. Same input plus same options always yield the same bytes.usecopydownloadzero-networkreproducibleok · copiedready · copiedLive
shipped · ready to shipsuccess
Pro tips for everyday utilities
Reach for crypto.getRandomValues
Cryptographically random for IDs, tokens, salts. Math.random is for animation and games, not security.
Mock data with seeds
Faker-style libraries can be seeded so tests are reproducible. Embed the seed in the fixture file.
Reference cards beat memory
Cheatsheets for Vim, Git, Docker, Linux signals are faster than man pages when you’re mid-flow.
Browser APIs vary
Touch events, gamepads, and clipboard differ across vendors. Feature-detect before use.
Persist in the right place
localStorage for user preferences, sessionStorage for transient state, IndexedDB for structured data.
When to track the mouse
Game UI, drag, gestures, tooltips.
Drag and drop
Track deltas during a drag operation. Random values come from crypto.getRandomValues — cryptographically secure for tokens, salts, and session IDs. Math.random is deterministic enough for animations but predictable enough to be a security bug.
CSPRNG-backedTooltips
Position tooltips relative to cursor. Pair with hashids, ULID, or UUID v7 when you need both random and sortable — useful for primary keys, public-facing IDs, and event log ordering without a sequence column.
reproducibleDrawing
Sketch on canvas using areaX/Y. Output is deterministic given the same seed, so fixtures and tests stay reproducible across CI runs and contributor machines. Embed the seed in the fixture file for full replay.
snappyGame prototypes
Movement speed matters for aim. Heavy work runs through useMemo so the UI stays snappy on large inputs. Same input + same options yields identical bytes — the kind of stability snapshot tests rely on.
feature-detectedHover heatmaps
Aggregate page coords to find hot spots. Storage tools persist to the right backend: localStorage for user preferences, sessionStorage for transient state, IndexedDB for structured data. Pick the right shelf and quota worries disappear.
deterministicQA
Diagnose flaky pointer tests. Browser feature detection: clipboard, fullscreen, gamepad, and Web Bluetooth APIs gracefully fall back when unavailable. No surprise white screens on Safari or older Firefox.
production-readyFrequently asked questions
Something missing?
Tell us what you need. We ship the top requests every two weeks.