File with .FNT extension contains generic font data used by Windows operating system in the form of vector or raster graphics file. Each glyph – a single font element – is a separate image file. Usually wrapped into executable file container with .FON extension for ease of installation.

For FNT files to be available in MS Windows operating system, they have to be installed to system fonts folder. This font format was replaced by fully scalable vector formats – TrueType (TTF file format) and OpenType (OTF file format) – largly due to being stored as somewhat limited bitmap image. There exist tools that offer option of converting above-mentioned formats into FNT files.