letsplay — NES

letsplay

Enter the password to continue.

letsplay· color tv

next switch

Drop an NES, Genesis, or SNES ROM (.nes / .md / .sfc) anywhere on the page (or Load ROM) to start.

Load ROM

🎮 Controller

Player 1 controls

Click an action, then press a key. Esc cancels.

Save states

Snapshot this game and jump back later. Online, only the host loads — both players jump to it. States are stored in your browser (IndexedDB); use ⤓ to download one as a file, or Import to add one.

How to play

Local 2-player: Load a ROM and play — both players share this keyboard.

Online: The host loads a ROM and clicks Host — that opens a panel to name the room, set the player count, and start. Friends click 🎮 Rooms, see the open game with its settings, and join in one click (no file needed; the host sends the game, and the player count is matched for you). For a private game, uncheck List in Rooms and share the room name — friends type it under Join by code.

Pick your player & roulette: Open ⚙ Settings to choose which character you play, and (host) turn on roulette — Share passes one character back and forth, Swap (co-op games) swaps who drives each character on a timer.

Reconnect & save: The host auto-saves every 10 s and reconnects automatically on a drop. Use 💾 Saves for manual save states — online, the host loads one and both players jump to it together.

Player 1: W A S D · J=A · K=B · Enter=Start · L-Shift=Select — remap under 🎮.

Player 2 (local only): Arrow keys · .=A · ,=B · R-Shift=Start · /=Select

Connection trouble? If joining is slow or play is laggy, run 🛰 Test connection below — it checks whether your network allows the fast (UDP) path.

Connection test

Checks how well your network reaches the WebRTC servers letsplay uses. UDP is the fast path for low-latency play; if it's blocked, you fall back to a slower relay (laggy). Nothing is sent to another player.

Click Run test to check your connection.

Game settings

Your name and character are your own. To start a game, set the room name and options, then Host game below. Players & roulette apply to everyone in the room, who must all use the same player count.

Your name

Room name (to host)

Players

List in Rooms (host)

Your character

Roulette (host)

Switch every 🎲 s

Your buttons (split)

↑ ↓ ← → A B Start Sel

Share = take turns on one character. Swap = both characters swap control on the timer. Split keys = two players share one character — each ticks the buttons they drive (e.g. one takes the D-pad, the other A/B).

Flash screen on swap (your view)

Advanced

Input delay (online) frames

Lockstep netcode (online)

Off = rollback: predicts remote input to hide latency, but a heavy Genesis/SNES core can hitch when jitter forces it to re-simulate. On = lockstep: never rolls back (no hitches), but adds steady input lag and briefly waits on a late packet. Host sets it for both. You can also switch mid-game from Pause.

🎮 Rooms

Open games you can jump into. Click one to join — the player count and settings come from the host, so you don't have to match them by hand.

Loading…

Have a private room code?

👋 Welcome!

Pick a name — it's how friends see you in a game. It's saved on this device, so you only set it once. You can change it anytime in the bar below.

⏸ Paused

Change the netcode settings, then Resume — both players briefly resync into the new mode.

Lockstep netcode (host)

Off = rollback (predicts, hides latency, can hitch on jitter). On = lockstep (no hitches, but steady input lag). Only the host sets the mode.

Input delay (you) frames