FSI file format description

Many people share .fsi files without attaching instructions on how to use it. Yet it isn’t evident for everyone which program a .fsi file can be edited, converted or printed with. On this page, we try to provide assistance for handling .fsi files.

4 filename extension(s) found in our database.

.fsi - FSI Viewer Configuration

The FSI configuration files are related to FSI Viewer. The FSI file is a FSI Viewer Configuration. NeptuneLabs FSI Viewer (short for "Flash based Single Source Image Viewer") is a web based viewer for high resolution images.

FSI Viewer
Configuration files
- / -
FSI Viewer Configuration related extensions:
NCSA Telnet Configuration File
Luppp Preferences Data
LyX Keymap Data
PerlCritic Runtime Configuration
Internet Sign-up Settings
Line 6 POD HD500X Edit Bundle

.fsi - F# Signature File

The FSI development files are related to Microsoft Visual Studio. The FSI file is a F# Signature File. F# is a mature, open source, cross-platform, functional-first programming language which empowers users and organizations to tackle complex computing problems with simple, maintainable and robust code.

Microsoft Visual Studio
Development files
- / -
F# Signature File related extensions:
Monotone Database
Visual Studio Content Data
Verilog Library
GCC Flags Data
CCXML Document
Microsoft Expression Web Home Page

.fsi - FME Feature Store Spatial Index Data

The FSI data files are related to FME Desktop. The FSI file is an FME Feature Store Spatial Index Data. FME Desktop is a flexible and powerful spatial ETL toolset used by thousands of GIS Professionals worldwide to quickly translate, transform, integrate data.

FME Desktop
Data files
- / -
FME Feature Store Spatial Index Data related extensions:
Inertial Explorer Heading Data
CryptoNG Encrypted File
Collaborative Computational Project Number 4 Format Data
Ash Ware Enhanced Behaviour Data
PhotoBase Album Data
Dpatch Patch Data

.fsi - FileSplit Data

The FSI data files are related to FileSplit. The FSI file is a FileSplit Data. FileSplit is a utility that splits large files into smaller files. The FileSplit seems to be no longer supported.

Data files
- / -
FileSplit Data related extensions:
SigmaScan Data
SpiderWEB Data
Rockbox Codec
Lotus CC:Mail Mailbox
AOL Instant Messenger Buddy List
FBB Initialization Settings Data

Naturally, other applications may also use the .fsi file extension. Even harmful programs can create .fsi files. Be especially cautious with .fsi files coming from an unknown source!

Can't open a .fsi file?

When you double-click a file to open it, Windows examines the filename extension. If Windows recognizes the filename extension, it opens the file in the program that is associated with that filename extension. When Windows does not recognize a filename extension, you receive the following message:

Windows can't open this file:


To open this file, Windows needs to know what program you want to use to open it. Windows can go online to look it up automatically, or you can manually select one from a list of programs that are installed on your computer.

To avoid this error, you need to set the file association correctly.

The .fsi file extension is often given incorrectly!

According to the searches on our site, these misspellings were the most common in the past year:

bsi, csi, dsi, esi, fci, fei, fi, fis, fs, fsk, fsl, fso, fwi, fxi, gsi

Is it possible that the filename extension is misspelled?

Similar file extensions in our database:

CR10X EdLog Source Code
FlexiSign Document
EtherCAT Slave Information File
Forth Source Code
HP PhotoSmart 850 Camera Firmware
USoft Application Resources Data

Operating systems

DataTypes.net currently supports the following operating systems:

Windows XP/Vista, Windows 7/8/10, Windows 11, CentOS, Debian GNU/Linux, Ubuntu Linux, FreeBSD, macOS, Mac OS X, iOS, Android

If you find the information on this page useful, please feel free to link to this page.


If you have useful information about the .fsi file format, then write to us!

DataTypes.net >> FSI file