Free interactive tool
Input Overlay Tester for Keyboard and Mouse
Check whether your browser can detect keyboard presses and left, middle, or right mouse clicks. The tester shows event names without storing what you type, and it gives you a quick preview of the raw input that can drive a stream overlay.
Recent input
Your latest ten browser inputs will appear here.
What this tool checks
Use the input overlay tester before building a stream scene
An input overlay depends on a simple chain: your keyboard or mouse creates an event, software detects that event, and a visual layer turns it into something viewers can understand. This free tester isolates the first part of that chain. Press a key and the page displays its browser event code. Click inside the test area and it records the mouse button. The counters help you confirm that repeated actions are reaching the page consistently.
The result is useful when you are evaluating a keyboard overlay for a tutorial, game stream, coding session, or live product demonstration. If the expected key appears here, browser input is working. If it does not, another application, browser permission, accessibility setting, or operating-system shortcut may be intercepting the action before the page receives it.
Browser versus Desktop
Why the tester only reacts while this page is active
Browsers deliberately limit global input capture. This page can react while it is open and focused, but it cannot watch keys in a game, OBS Studio, a design app, or another browser tab. That boundary protects visitors from websites silently monitoring system-wide input. It also means an online input overlay tester is a diagnostic tool, not a complete broadcasting source.
Overlay Cat Desktop handles the streaming workflow. The installed app listens for supported system-level keyboard, mouse, arrow-key, or gamepad input and renders the selected Bongo Cat character locally. It then provides a local source that can be added to OBS Studio or TikTok LIVE Studio. Use this browser tool to understand the input vocabulary, then use the Desktop app when the overlay must keep reacting while another application has focus.
The tester keeps its short activity history in the current page state. It does not send typed characters, specific keys, mouse positions, or the event history to Overlay Cat analytics.
Streaming use cases
What keyboard and mouse visibility adds to a stream
In a software tutorial, a visible keyboard action confirms which shortcut opened a panel or ran a command. In a speedrun or rhythm game, viewers can connect timing on screen with the player's physical input. In a coding stream, the overlay can make navigation and editing shortcuts easier to follow without covering the code itself. A reactive Bongo Cat adds the same information with more personality than a plain keystroke list.
The best layout depends on the scene. A full keyboard works when viewers need broad shortcut context. A compact keyboard is easier to fit beside gameplay or inside a vertical TikTok LIVE frame. Arrow-key and gamepad styles are more focused, while a mouse-and-keyboard style helps with design, browsing, and productivity demonstrations. Browse the keyboard overlay guide or compare the Bongo Cat overlay templates before choosing a format.
Move from test to stream
Turn detected input into a Bongo Cat overlay
Download Overlay Cat Desktop for macOS, Windows, or Linux, choose a character and input style, then connect the local output to your broadcast software. The browser tester is free to revisit whenever you need to confirm a key or mouse button name.