Filee formats and engines: choose a conversion route
Check the direction of a conversion and its engine requirement before downloading a large component.
On this page
An extension list is not a conversion guarantee
Filee supports images, documents, media, archives and other file types. Its official README maps inputs to outputs, and the engine documentation describes the exceptions. Read a row as a directional route, not permission to convert any listed file into every other format.
A damaged, encrypted or DRM-protected file can fail even when its extension appears in a list. Filee's release notes say encrypted and copy-protected files cannot be converted. Renaming the extension does not change the file's contents.
Common routes and their dependencies
| Task | Documented route | Engine or important limit |
|---|---|---|
| Change an ordinary image format | JPG, PNG, WebP, TIFF and other image routes | Built-in image support; writing HEIC uses FFmpeg |
| Make a PDF from images | Images to PDF | Built-in PDF support |
| Read PDF pages as pictures | PDF to PNG or JPG | Built-in PDF rendering |
| Get editable text from PDF | PDF to DOCX or TXT | Reading-order text; text extraction has no OCR |
| Put PDF pages in a presentation | PDF to PPTX | Each page is a picture; page text goes in speaker notes |
| Convert newer Office files to PDF | DOCX, XLSX, PPTX to PDF | Built-in readers and bundled rhwp; Microsoft Office is not used |
| Handle older or rare office formats | Legacy DOC/PPT and additional office routes | Some routes need optional LibreOffice |
| Transcode video or audio | MP4, MOV, MKV and audio routes | Optional FFmpeg |
| Convert markup formats | Additional Markdown/LaTeX/Org routes | Some routes need optional Pandoc |
| Work with PostScript | EPS or PS to PDF | Optional Ghostscript |
| Handle rare e-book formats | LIT, LRF and other listed formats | Optional calibre |
This is a selection for choosing a route, not the full format catalog. Check the official format table and engine reference for your exact input and output.
Find what your installation can offer
Open Settings, Engines to inspect installed engines and their status. When multiple engines handle a route, their priority matters. Filee chooses a route automatically; engine order can change which implementation handles the file.
A missing component can be shown on a format slice as a requirement such as Needs LibreOffice. Install the engine for the route you need instead of downloading everything in advance. The installer bundles smaller engines; optional downloads can be much larger. Engine availability and automatic downloads differ by platform, so use the current engine page for the system you are running.
The CLI can inspect formats too:
filee formats heic
filee formats
The first command asks what HEIC can become. The second lists format identifiers and extensions. The official CLI documentation says these listings also include routes an optional engine would add, so a listed target alone does not prove that its engine is already installed.
Check what the target will lose
Converting a file changes its representation. PDF-to-DOCX text can lose tables and styling; PDF-to-PPTX preserves a page as a picture but does not make its elements editable. A video-to-image route and a video-to-video route have different outputs. A raster-to-vector trace is not the original illustration's editable source.
For animated images, the engine documentation describes preservation of frames for supported animated targets. Other image targets can receive the first frame. Choose the target for the feature you need and inspect a short sample before a batch.
Offline conversion still needs preparation
The project says file conversion stays on the computer and Filee does not upload files or send usage telemetry. That does not mean the program never connects: it checks GitHub for updates and downloads optional engines when requested. Its automatic update check can be disabled in Settings, About.
Install the required engine before going offline, then test the intended route with a non-sensitive sample. This wiki's web analytics policy is separate from the desktop software's policy. Read the project's README privacy section for the application and our privacy page for this site.
If an installed engine still produces a poor document or fails on one file, use the troubleshooting checklist. Keep the source and report a reproducible problem rather than assuming another engine will preserve every feature.
Why 244 formats does not mean every pair works
The 1.12.0 README lists 244 readable formats across 17 categories. A font is not a source for an editable Word document, and an archive is not a video codec. In the original Reddit discussion, the developer explicitly clarified that font conversion is between font formats. Start with filee formats <source> or the official catalog for the output choices, then inspect the engine requirement.
For example, HEIC input and HEIC output are not symmetric: reading a photo uses image support, while writing HEIC uses FFmpeg. Modern Office-to-PDF routes can use built-in readers and the bundled renderer; installing LibreOffice does not automatically mean that it handles every Office conversion.
Use an engine that is already on the computer
Settings, Engines can show a compatible existing copy and lets you choose Use my copy. The documented lookup prefers a copy you explicitly selected, then Filee's own copy, then a discoverable system installation. The app can warn when the discovered version is older than its tested download.
Some platforms do not have an in-app download for every optional engine: the reference lists FFmpeg/Ghostscript on macOS and LibreOffice/Ghostscript on Linux as cases that use an existing installation. Inspect your platform's engine status instead of looking for a button from a Windows screenshot.
Avoid changing all engine priorities at once while debugging. Record the original order, change the relevant route, compare one sample, and retain the result's limits. For live formulas, a successful spreadsheet conversion still has the documented cached-results limitation.