Compare Microsoft Flight Simulator and FSX on graphics, realism, hardware, offline use and add-ons, with clear advice on which one to choose.
FSX is the 2006-era Microsoft Flight Simulator X, while “Microsoft Flight Simulator” in modern comparisons usually means MSFS 2020 or MSFS 2024. FSX is lighter, offline-friendly and rich in legacy add-ons; modern MSFS offers a streamed world, much better visuals, live weather, newer avionics and broader platform support.
What does Microsoft Flight Simulator mean in this comparison?
FSX is itself a Microsoft Flight Simulator, so the comparison is really between Flight Simulator X and the modern MSFS generation. MSFS 2020 and MSFS 2024 are separate products rather than updates or editions of FSX.
If MSFS 2020 is the version you are considering, our detailed comparison of MSFS 2020 and FSX covers that pairing specifically. MSFS 2024 changes content delivery, career activities and several simulation systems; our breakdown of the differences between MSFS 2020 and 2024 explains those changes separately.
What are the main differences between FSX and modern MSFS?
The largest differences are the scenery technology, software architecture, internet dependence and supported platforms.
| Area | FSX | MSFS 2020 and 2024 |
|---|---|---|
| Core technology | Legacy 32-bit Windows simulator | Modern 64-bit simulators |
| World scenery | Mostly locally installed landclass, autogen and scenery packages | Satellite-derived terrain, photogrammetry in supported areas and streamed world data |
| Graphics and weather | Older rendering, clouds, lighting and ground detail | Volumetric clouds, modern lighting, live weather and far greater world detail |
| Internet use | Well suited to routine offline flying | Offline options exist, but the best scenery and online services require a connection |
| Platforms | Windows PC | MSFS 2020: PC and Xbox Series X|S; MSFS 2024: PC, Xbox Series X|S, PS5 and PS5 Pro |
| Add-ons | Large legacy library built over many years | Separate modern add-on formats and active marketplaces |
| Hardware demands | Lower overall, but limited by an old, heavily main-thread-dependent engine | Much higher CPU, GPU, storage and network demands |
Modern MSFS has the stronger baseline flight and environmental simulation, but aircraft quality still matters. A carefully developed FSX aircraft can model procedures and systems more deeply than a basic modern default aircraft, so the simulator's age alone does not determine cockpit realism.
Which simulator should you choose?
Choose modern Microsoft Flight Simulator for most new setups; choose FSX when offline use, older hardware or an existing FSX add-on collection matters more than visual fidelity.
Choose FSX if:
- You already own aircraft, scenery and utilities made specifically for FSX.
- You want locally installed scenery without depending on continuous world streaming.
- Your PC cannot meet the substantially higher demands of MSFS 2020 or 2024.
- You use a specialist legacy add-on or cockpit setup that has no supported modern replacement.
Choose MSFS 2020 or 2024 if:
- You want convincing terrain, cities, lighting, clouds and live weather without rebuilding the simulator through numerous scenery packages.
- You need native support for a modern console or PC VR headset.
- You prefer newer avionics, active platform development and modern multiplayer services.
- You are starting without an established FSX library.
On PlayStation, there is no FSX or MSFS 2020 choice: MSFS 2024 is the only Microsoft Flight Simulator released for PS5 and PS5 Pro.
Can FSX add-ons be used in modern Microsoft Flight Simulator?
FSX aircraft and scenery cannot normally be copied into MSFS 2020 or 2024 because the model, gauge, scenery and software interfaces are different.
A common mistake is to copy an FSX aircraft from SimObjects, or an old scenery package from Scenery, into a modern simulator's Community folder. Even if some textures appear, the aircraft systems, animations, materials, sounds or compiled modules will usually fail. Our FSX add-on compatibility explanation covers what must be rebuilt or converted by its developer.
Physical controls are a different matter. Many USB yokes, throttles and pedals can be reused if the operating system still has suitable drivers, although control assignments and sensitivity curves must be configured again.
Will FSX run better on an older PC?
FSX usually needs less powerful hardware, but its age does not guarantee smooth performance on a modern or older computer.
- Main-thread limits: dense autogen, traffic and complex aircraft can reduce frame rates even when the graphics card is barely loaded.
- 32-bit memory ceiling: combining detailed scenery, large textures and complex aircraft can exhaust FSX's address space and produce an out-of-memory crash.
- Legacy software problems: old installers, gauges and modules may depend on retired components or protected Windows folders.
- Modern MSFS streaming problems: blurry terrain or delayed scenery can result from disabled online data, limited bandwidth or cache trouble rather than weak graphics hardware alone.
Do not compare the simulators using only their minimum hardware requirements. FSX favours strong per-core CPU performance and careful add-on management, while modern MSFS needs a balanced CPU, GPU, memory, storage and network connection.
Can both simulators be used offline?
Both can provide some form of offline flying, but FSX is the better choice for a consistently local setup.
FSX's normal flights, aircraft and installed scenery do not rely on streamed world data. Modern MSFS has offline data and locally installed content, but authentication, package availability and platform settings can affect access, and offline scenery lacks much of the detail seen with online services enabled. MSFS 2024 relies especially heavily on streamed content.
Is FSX still worth using?
FSX remains useful for established installations, low-demand offline flying and specialist legacy add-ons, but it is difficult to recommend as the default starting point for a newcomer.
Its huge back catalogue and modest base hardware requirements still have value. The trade-off is an old 32-bit engine, dated default scenery and extra work to keep legacy software stable; our practical guide to starting and maintaining FSX explains those limitations in more detail.