SMS Plus GX

MASTER SYSTEM & GAME GEAR EMULATOR CORE

SMS Plus GX

SMS Plus GX is a Libretro core that emulates Sega Master System and Game Gear hardware for frontends that implement the libretro API (for example RetroArch). It is an improved libretro port of the SMSPlus-GX codebase and is distributed as a core that frontends can download and run.

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SMS Plus GX emulator screenshot.

Master System & Game GearPRIMARY SYSTEM

History documentedPROJECT BEGAN

Open sourcePROJECT MODEL

WHY IT MATTERS

Why use SMS Plus GX?

Provides a focused Master System / Game Gear emulation core maintained under the libretro ecosystem. Useful when you want a dedicated MS/GG core in a libretro frontend rather than a combined all-in-one Sega core.

BEST FOR

Best for

Users of RetroArch or other libretro frontends who want a dedicated Master System / Game Gear core with the libretro feature set (core options, savestates, shaders, rewind/netplay via the frontend).

The people behind SMS Plus GX

History & status

SMS Plus GX is the libretro-port of the SMSPlus-GX project. The core is maintained in the libretro organization and appears in the official Libretro documentation and core lists. Development and packaging are handled via the libretro project repositories (smsplus-gx on GitHub/GitLab). The core continues to be distributed through the libretro core infrastructure (Core Downloader / core distribution manifests) and is available for common RetroArch platforms. Because it is a libretro core, its active maintenance and release cadence follow the libretro core packaging process rather than a separate standalone application release schedule.

What SMS Plus GX supports

Libretro frontends (RetroArch and other libretro frontends)
Windows (via RetroArch)
Linux (via RetroArch)
macOS (via RetroArch)
Android (via RetroArch)
Other platforms supported by RetroArch where the core binary is provided (e.g., some handheld Linux OS builds, third-party builds)

Download and availability

OFFICIAL DOWNLOADS

Get SMS Plus GX

Official distribution for users is via libretro cores (RetroArch Core Downloader or the libretro core distribution). Do not expect a separate packaged emulator executable — obtain SMS Plus GX through your libretro frontend’s core management tools or the libretro core download archives.

Get SMS Plus GX ↗

DOCUMENTATION

Official documentation

Read the official configuration, compatibility, and troubleshooting material before changing advanced options.

Read official documentation ↗

Broken or missing download? Emulator projects move and official links sometimes change. Please contact Retro Replay so the source can be verified and updated.

SMS Plus GX setup guide

Setup note: This setup guide assumes you will run SMS Plus GX inside a libretro-compatible frontend such as RetroArch. It describes how to obtain the core, prepare optional system BIOS files, and load games with recommended settings.

1) Install a libretro frontend (RetroArch recommended): Install RetroArch for your platform using the official RetroArch distribution channels (RetroArch website / platform package manager / app store). Ensure the frontend is a recent build so it can download and run current cores.
2) Download the SMS Plus GX core: Open RetroArch, go to Online Updater → Core Downloader, then locate the Sega – MS/GG entry corresponding to SMS Plus GX and download it. Alternatively, use the libretro core archives/manifests to obtain the core binary for platforms where the core is distributed. Do not download unofficial executables claiming to be SMS Plus GX outside libretro packaging.
3) Prepare BIOS (optional): SMS Plus GX can attempt to load a Master System BIOS (e.g., bios.sms) when the core option for SMS BIOS is enabled or set to auto. A BIOS is optional for many ROMs but may be required for accurate region boot behaviour or certain protected titles. The core and documentation indicate the BIOS is attempted when the core option is configured. BIOS files are not distributed with the core; if you own the original firmware, place the BIOS file in the location your frontend expects (RetroArch’s system/BIOS directory) and name it according to the frontend/core guidance.
4) Load a ROM: From RetroArch, use Load Content and choose a Master System or Game Gear ROM (supported container extensions include .sms, .gg, .bin and compressed archives like .zip/.7z if the frontend supports them). After loading, RetroArch will ask which core to use—select SMS Plus GX if it is installed.
5) Configure core options and controls: With content loaded, open the Quick Menu → Options to configure SMS Plus GX core-specific settings (region handling, BIOS use, FM sound options, mapper/compatibility options). Configure input mapping in Quick Menu → Controls or in the frontend Input settings. Some options (for example FM sound channel settings or specific mapper patches) can affect audio/compatibility; change them if a particular game requires it.
6) Advanced: BIOS location and core file details: Place any BIOS files in RetroArch’s system directory (or the path your frontend documents). The libretro core expects the BIOS filename and location to match the frontend’s core-info mapping; confirm via the core info / documentation if uncertain. Do not place commercial BIOS or copyrighted firmware unless you own it.
7) Troubleshooting and alternatives: If a game fails to run or audio/mapper behaviour is wrong, try switching to another MS/GG libretro core (for example Genesis Plus GX for Game Gear compatibility) or try a different core build. Check the core’s repository and libretro documentation for known issues and core options.

Software reminder: The core does not include commercial games or BIOS images. Acquire game ROMs and BIOS files only if you legally own the original media. Follow your frontend’s documentation for BIOS filename/location requirements.

Sources and further reading

Detailed guides and tutorials

Explore step-by-step guides for SMS Plus GX as they are published.

Use SMS Plus GX on Android

An Android ARM64 Libretro build exists for SMS Plus GX. Run the core through RetroArch for Android; the standalone desktop download and Android core may have different menus and features.

Emulates: Sega Master System, Game Gear.

Verified Android core build ↗ · Browse all Android emulators →