Leaf Viewer
The Leaf Viewer mark: a pinnate leaf

Leaf Viewer

A read-only document reader for Windows.

Leaf for short. Double-click a file and it opens, typeset, with the headings on a rail. It never writes to your files and never contacts a server.

Get it free on the Microsoft Store What it reads

Free for now · Windows 10 and 11 · no telemetry

A Markdown file about Leaf itself, rendered: typeset prose, a numbered equation, a table and a task list, with a contents rail. A Mermaid flowchart showing what Leaf does with each kind of file, drawn by the reader. A short LaTeX paper titled On Opening a File and Simply Reading It, with its equation typeset and numbered. A Jupyter notebook with executed cells and a bar chart of Leaf's format families. A PDF open in Leaf, one page drawn, its bookmarks nested in the contents rail. CP437 text art on a fixed grid, decoded the way it was drawn, in the night theme. A CSV file drawn as a table, numeric columns right-aligned, with a row and column count beneath.

Mathematics, set

Equations are typeset. Numbered ones go in the rail, so (3.17) is somewhere you can jump to.

It never phones home

No telemetry, no accounts, no update pings. It makes no network requests at all.

It never writes

Read-only by design. Edit in whatever you use; Leaf re-renders when you save and keeps your place. It still prints, and saves as a PDF.

From the Store

Installed, signed and updated by Microsoft. It opens the file types you pick, and nothing else.

Look under anything

Ctrl+U shows the file as written, highlighted. Again for the document. Offered only where there is something underneath: a Python file is already its own source.

The same Markdown document shown as highlighted source, with line numbers.

What it reads

178 extensions, rendered rather than dumped. Anything unrecognised opens as plain text.

Markdown

Tables, footnotes, task lists, mathematics.

.md.markdown.mdx.qmd.rmd

LaTeX

Prose and sections, the mathematics set.

.tex.ltx

Notebooks

Cells, outputs, figures, tracebacks.

.ipynb

Diagrams

Drawn by Mermaid and Graphviz, in your accent.

.mmd.mermaid.gv.dot.svg

Structured text

Headings become a contents rail.

.adoc.rst.org.typ

PDF

Page by page, text selectable, links live, bookmarks in the rail.

.pdf

Records

Calendars, contacts, mail, cue sheets — as tables.

.ics.vcf.eml.po.cue.fountain

Data and diffs

Columns aligned, delimiters measured. Diffs coloured.

.csv.tsv.psv.diff.patch

Source

Sixty grammars, with line numbers.

.py.js.rs.go.sql+115

Subtitles

A timed cue table.

.srt.vtt.ass.ssa

Artwork

Code page 437, on a fixed grid.

.nfo.diz.ans

Free while it is new

It will be US$11.99 later. Get it now and it stays free for you.

  • Free forever once you have it, updates included
  • The price is for people who come later, never for you
  • No subscription, no account, no telemetry

Get it on the Microsoft Store

Windows 10 and 11. If the Store cannot find it yet, the listing is on its way.