Contra
Your own Contra (USA) ROM. The 131,072-byte ROM body must hash sha1 979494e7869ac7ab4815fdbd1dc99f893f713fbf; a plain iNES or a NES 2.0 header are both accepted and identify the same cartridge. It is read in your browser and never uploaded.
Files are read on this device. They are never uploaded.
Keyboard and mouse recommended.
The game downloads only after you press Play. Sound starts off.
Controls
| Arrow keys | move and aim |
| X | A (jump) |
| Z | B (fire) |
| Enter | Start |
| Shift | Select |
| Gamepad | any standard controller, detected automatically (untested) |
| Touch | EmulatorJS on-screen NES pad on phones and tablets (untested) |
Contra has no battery save — the cartridge has no save chip, which is why the game itself has no save feature. This page instead keeps an emulator save state in your browser, under this site's storage, keyed by your ROM's own SHA-1; it is written every 10 seconds and restored when you come back. It is a save state, not a battery save, and clearing site data removes it. Save inside the game before exporting a backup. Clearing browser data can erase progress.