A free Windows desktop app for cheap Bluetooth LED strips.
Colors, effects, screen sync, music, hotkeys, OBS, AI assistants, notification alerts — no
phone, no hub, no account.
RGBZap controls ELK-BLEDOM-style Bluetooth LED strips — the ones sold with phone apps like duoCo Strip / Lotus Lantern and a little IR remote — straight from your PC over Bluetooth LE.
- Light — color picker, presets, your own saved colors, brightness, and scenes (save a color + brightness + effect under a name, apply it in one click).
- Effects — every effect as a live preview tile, so you see what it does before you pick it. Ambient drifts (Aurora, Lava lamp, Vaporwave, Sunset, Forest, Galaxy, Ice, Rainbow, Ocean); flames & pulses (Candle, Torch, Fire, Breathe, a 4-7-8 breathing guide, Heartbeat, Neon flicker, Lightning, Fireworks, Police, Party); plus the strip's own built-in jump / crossfade / blink modes.
- Screen Sync (Ambilight) — the strip follows a monitor's color in real time. Picks the dominant color so scenes pop instead of averaging to mud, and keeps a dim glow on dark scenes. Great for movies and games. Ignores black bars on widescreen films, and can sample just the edges (bias lighting) or one side of the screen.
- Audio reactive — pulse, beat flash, beat colors, spectrum, or pitch, from whatever your PC is playing.
- Global hotkeys — turn the lights on/off, dim or brighten, switch scenes, and start or stop screen sync from anywhere, even in a full-screen game. Every shortcut is yours to change.
- OBS link — red while you stream or record, and a different look for each OBS scene. Uses OBS's built-in WebSocket server (OBS 28+), no plugin.
- Command line & local API —
rgbzap color red,rgbzap scene "Movie night". Drive the lights from Stream Deck, AutoHotkey, scripts, or a build-status light. See below. - AI assistants (MCP) — let Claude or any MCP-capable assistant set colors, scenes and effects ("warm and dim, I'm watching a film") or flash the strip when a long task ends.
- Notification & call alerts — a quick flash when a notification arrives, a green pulse while a call rings (Phone Link, Teams, WhatsApp, Discord…), then the strip goes back to exactly what it was doing.
- Comfort — colors fade into each other instead of snapping, and Reduce flashing softens fast effects, alerts and screen-sync cuts for anyone sensitive to flashing lights. A color balance control fixes strips whose "white" looks pink or blue.
- Lights off with your PC — switches the strip off when you shut down, restart or sign out (and brings it back if Windows cancels the shutdown). On by default; untick it in System if you'd rather the strip stay as it is.
- Multiple strips — scan, pick yours from a list, and RGBZap remembers it. Connects automatically on launch and reconnects by itself if the link drops. Strip not listed? Tick Show all Bluetooth devices and pick it from there.
- Update notices — a banner tells you when a new version is out (optional, see Privacy).
- Lives in the tray — close the window and it keeps running; right-click the tray icon for colors, scenes, effects, brightness, and screen sync. Optional start with Windows.
From the latest Release, grab either:
RGBZap-Setup-<version>.exe— the installer. No admin rights needed; adds a Start menu entry, an optional desktop shortcut, optional start-with-Windows, and a normal uninstaller (Settings › Apps).RGBZap-<version>-windows.zip— portable. Unzip anywhere and runRGBZap.exe.
"Windows protected your PC"? RGBZap is new and not code-signed yet, so SmartScreen doesn't recognize it. Click More info → Run anyway. The full source is right here if you'd rather check it — or run it from source below.
pip install -r requirements.txt
python elk_gui.py
Python 3.10+ on Windows. Launch RGBZap.bat opens it without a console window.
elk_control.py is a separate, direct-to-the-strip tool (it can't run while RGBZap is
connected — a strip takes one connection at a time):
python elk_control.py scan
python elk_control.py color 255 0 0
python elk_control.py on
To control a running RGBZap, use rgbzap / python rgbzap_cli.py (see below).
- Power on the strip.
- Close the phone app (and don't pair the strip in Windows Bluetooth settings) — a strip accepts only one Bluetooth connection at a time, so anything else holding it hides it from the scan.
- Open RGBZap. It finds your strip, connects, and remembers it. Got more than one? Tap ↻ on the Light tab and pick from the list.
Open the Tools tab. These work from anywhere once RGBZap is running; press Change beside one to pick your own.
| Action | Default |
|---|---|
| Lights on / off | Ctrl+Alt+Home |
| Brighter / Dimmer | Ctrl+Alt+PgUp / Ctrl+Alt+PgDn |
| Screen sync on / off | Ctrl+Alt+End |
| Audio reactive on / off | Ctrl+Alt+Ins |
| Next / previous scene | Ctrl+Alt+Shift+→ / Ctrl+Alt+Shift+← |
If a shortcut doesn't work, another program already owns it — RGBZap tells you, and you can pick a different one. Shortcuts need Ctrl, Alt or Win, so ordinary typing is never touched.
In OBS turn on Tools › WebSocket Server Settings › Enable WebSocket server, then tick Connect to OBS in RGBZap's Tools tab and enter the port and password. You can have the strip go red while you stream or record, and pick a RGBZap scene for each OBS scene with Scene lighting…. RGBZap only listens; it can't change anything in OBS.
Tick Let other programs control RGBZap in the Tools tab (it's off by default), then:
rgbzap status
rgbzap on rgbzap off
rgbzap color red rgbzap color "#ff8800" rgbzap color 255 136 0
rgbzap brightness 40
rgbzap scene "Movie night" rgbzap scenes
rgbzap effect Aurora rgbzap effect off rgbzap effects
rgbzap sync on|off|toggle rgbzap audio on|off|toggle
rgbzap flash green # a short alert flash, then back to what it was
rgbzap.exe is installed in the cli folder inside RGBZap's folder; tick Add the rgbzap
command to PATH in the installer to use it from any terminal. It reads the port and secret token from RGBZap's
settings, so there's nothing to set up. Exit code 0 means it worked.
The same thing is a small HTTP API for other tools: http://127.0.0.1:49732, with the
token as Authorization: Bearer <token> (Tools tab › Copy token), JSON bodies like
{"color": "red"}. It only listens on your own PC, needs the token, refuses requests that
come from web pages, and can only do what RGBZap's own buttons can.
rgbzap mcp is a Model Context Protocol server, so an AI
assistant can use the same controls as the command line. Turn on Let other programs
control RGBZap in the Tools tab, press Copy AI assistant setup, and paste the line into
a terminal. For Claude Code it looks like:
claude mcp add rgbzap -- "C:\Users\you\AppData\Local\Programs\RGBZap\cli\rgbzap.exe" mcp
For other apps (Claude Desktop, Cursor…), add a stdio server whose command is that
rgbzap.exe with the single argument mcp. The assistant gets ten tools: status, list,
power, color, brightness, scene, effect, flash, screen sync and audio. It goes through the
local API above, so it needs the switch on, only works on this PC, and can do only what
RGBZap's own buttons can.
Versions from 1.0.1 on show a banner when a new release is out. Click it, download the new
RGBZap-Setup-<version>.exe and run it — it upgrades in place and keeps your settings.
(1.0.0 has no update check, so install 1.0.1 or newer by hand once.)
- Windows 10 or 11
- Bluetooth LE (built in on most laptops; a cheap USB BLE dongle works on desktops)
Works with the common classic ELK-BLEDOM protocol (9-byte 0x7e…0xef frames):
ELK-BLEDOM, ELK-BULB, MELK, XSL-, "LED LIGHT STRIP", and similar. RGBZap
auto-detects the write characteristic (fff3 / ffe1 / Nordic-UART) on connect, so it
adapts to more variants than a hardcoded one.
Honest caveat: it's only verified on a real ELK-BLEDOM. A few models (e.g. some LEDBLE variants) use a different byte order — the app connects but colors may look off. If your strip connects but misbehaves, open an issue with its advertised name.
Everything stays on your PC. RGBZap has no account and no telemetry. The only internet request it makes is an update check: about once a day it asks GitHub whether a newer release exists, sending just a standard web request (the app name and version). It never downloads or installs anything by itself — if there's a new version you get a banner and download it yourself. Turn it off any time in System › Updates. Notification alerts are off by default; when you turn them on, RGBZap reads new notifications on your PC only to tell whether one arrived or a call is ringing — nothing is stored or sent anywhere. The local API is off by default, only listens on this PC and needs a secret token. The OBS link talks only to an OBS on the host you enter (normally this PC). Global hotkeys register only the exact shortcuts you see in the Tools tab; RGBZap never sees other keys you press.
Your settings and remembered strip live in %APPDATA%\RGBZap — delete that folder to
reset RGBZap. That includes the local API token and, if you use the OBS link, your OBS
password, so treat that folder as private.
- DRM video (Netflix, Disney+, etc.) captures as black on Windows, so Screen Sync can't read it and fades to a dim glow. Local players, browsers, and YouTube work.
- Call detection reads the notification's wording ("Incoming call", "is calling", …), so it currently works for English-language notifications.
- Reduce flashing switches off the strip's own Blink and Jump effects, because they run inside the strip where RGBZap can't soften them.
py -m pip install -r requirements-dev.txt
build.bat
Produces in dist\: the RGBZap\ app folder, a portable RGBZap-<version>-windows.zip,
and — if Inno Setup 6 is installed
(winget install JRSoftware.InnoSetup) — the RGBZap-Setup-<version>.exe installer.
The version comes from APP_VERSION in elk_gui.py.
The strip protocol comes from the excellent dave-code-ruiz/elkbledom Home Assistant integration (MIT) — see THIRD_PARTY_NOTICES.md. RGBZap is a standalone desktop app built on the same frames.
Made by Dilshan Rangaka. RGBZap is MIT licensed — see LICENSE.