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Play NES Online - Help & FAQ

Welcome to the **Play NES Online Help Desk**. Here we address the most common technical questions regarding controller configurations, gamepad compatibility, saving your game progress, and browser performance optimization.

1. Gamepad and Input Troubleshooting

How do I play with a physical game controller?

Our emulator natively supports modern USB and Bluetooth controllers (including Xbox, PlayStation, and Nintendo Switch controllers) via the browser's **HTML5 Gamepad API**. Plug in or pair your controller, press any button to wake it up, and the emulator will automatically map it to the NES controls. You can verify connection status in the "Controller Management" panel in the right sidebar.

What are the default keyboard controls?

• Player 1: D-Pad: **Arrow Keys** | A Button: **X** | B Button: **Z** | Select: **Right Ctrl** | Start: **Enter**
• Player 2: D-Pad: **W, A, S, D** | A Button: **K** | B Button: **J** | Select: **Tab** | Start: **Space**

You can customize these keys by opening the **Controller Management** sidebar drawer and clicking any button field to assign a new key.

2. Game Save States (IndexedDB)

How do I save my progress?

You can use the **Save State** feature by pressing **F5** or clicking the **Save** button in the "Session Quick-Actions" panel. This captures the exact state of the emulated console RAM and saves it instantly.

Where are my saves stored?

All saves are written directly into your browser's sandboxed local database using **IndexedDB**. They are never uploaded to our servers, keeping your data entirely private. However, clearing your browser's history or cookie storage database completely might delete your save states. You can download local backups to your desktop to prevent loss.

How do I load a saved game?

Press **F9** or click **Load** in the sidebar to resume from your last save point instantly.

3. Video and Audio Performance

Why is my game speed lagging or stuttering?

If you experience frame rate drops, try the following optimizations:

• Ensure **Hardware Acceleration** is enabled in your browser settings (Chrome/Edge: Settings -> System -> Use graphics acceleration when available).
• Close background applications, heavy tabs, or active downloads.
• If using a laptop, plug in the charger and change power settings to "High Performance" (battery saver modes throttle CPU performance).

Why is the game audio crackling?

Audio crackling occurs when the browser's Web Audio buffer runs out of samples. This happens if the CPU is momentarily overloaded or if the display refresh rate causes the browser to throttle the emulator loop. Ensure hardware acceleration is active, and avoid resizing the browser window during active play.