Copperline runs directly in your browser using WebAssembly. The default configuration is an Amiga 500 (512 KB Chip RAM + 512 KB Slow RAM) running the bundled open-source AROS Kickstart replacement. Use the Machine and Video controls in the sidebar to switch between an Amiga 500 and AGA Amiga 1200, or toggle PAL and NTSC modes. You can insert your own floppy disk images (.adf, .adz, .dms, .ipf, .scp) with the Insert DF0 button, or provide a custom Kickstart ROM.

Save states allow you to snapshot the complete emulated machine state. Quick save keeps a state in browser storage that persists across visits, while Save state downloads a standard .clstate snapshot file compatible with Copperline desktop builds. You can also load disk images directly from a URL via DF0 from URL or by appending ?df0=<url> to the page address (requires CORS support on the host). All emulation runs entirely client-side on your device.

Customise CRT shaders, display scaling, overscan, and monitor bezels in the Display settings. Click the emulated screen to capture the mouse pointer (press Esc to release, or hold Esc to exit fullscreen). Toggle the Joystick button to control port 2 using the keyboard (arrow keys and Right Ctrl/Alt) or virtual touch controls on mobile devices. An on-screen Amiga keyboard can be opened with the Keyboard button.

Floppy disks are write-protected in the browser build. Official Commodore Kickstart ROMs are copyrighted and not included; please use ROMs dumped from your own hardware. The bundled AROS ROMs are distributed under the AROS Public License. If you encounter an issue, click Report a bug in the top navigation to file a pre-filled report on GitHub.