Supported File Formats

Each application's own format is the Office Open XML format of its Microsoft Office counterpart: .docx for Impulse, .xlsx for Formula, .pptx for Expo (and Nu). Methodox Office reads and writes these as its native formats, not through a conversion, and writes back the parts of a file it does not understand unchanged, so a document can go between Methodox Office and Microsoft Office without losing what Methodox Office does not edit.

Whenever a file is opened or saved, the status bar says Nothing lost or how many problems there were; click it for the list. On the command line each problem is a Warning: line on standard error. A format no application handles is refused with a message and nothing is written.

At a glance

Application	Opens	Saves	Exports
Impulse	`.docx` `.doc` `.dot` `.rtf` `.odt` `.html` `.htm` `.txt` `.md` `.markdown`	`.docx` `.rtf` `.odt` `.html` `.htm` `.txt`	PDF
Formula	`.xlsx` `.xlsm` `.csv`	`.xlsx` `.xlsm` `.csv`	PDF
Expo	`.pptx`	`.pptx`	PDF, PNG, JPEG, SVG (one slide), plain text
Nu	`.pptx` `.drawio` `.dio` `.odg` `.vsdx` `.vsdm` `.svg` `.drawio.png`	`.pptx` `.drawio` `.dio` `.svg` (one page)	PDF, PNG, JPEG
Math	`.mml` `.smf` `.txt`	`.mml` `.smf` `.txt`	PDF, PNG, JPEG

Not supported yet in any application: Excel and PowerPoint 97-2003 (.xls, .ppt), .xlsb, OpenDocument spreadsheets and presentations (.ods, .odp), Office templates (.dotx, .xltx, .potx), macro-enabled Word and PowerPoint files (.docm, .pptm) and EPUB. Word 97-2003 (.doc, .dot), LibreOffice Draw (.odg) and Visio (.vsdx, .vsdm) files open read-only, to be saved in another format.

Which application a document goes to, from the Start Centre or mos, follows its extension: .docx .doc .dot .txt .rtf .odt .html .htm .md .markdown to Impulse, .xlsx .xlsm .csv to Formula, .pptx to Expo, .svg .drawio .dio .odg .vsdx .vsdm to Nu, and .mml .smf to Math; so does dropping a file on any window. A .pptx opens in Expo; open it from Nu to edit it as a drawing. The installer can associate .docx, .doc, .rtf, .odt and .md with Impulse, .xlsx, .xlsm and .csv with Formula, .pptx with Expo, .drawio and .dio with Nu, and .mml with Math.

Methodox Impulse

Format	Open	Save	Notes
Word document `.docx`	yes	yes	The native format. A document opened and saved without changes keeps every part of the package as it was; parts Impulse does not model, content controls among them, are written back unchanged. Tracked changes and comments go both ways with Word. Strict Office Open XML opens and is saved as Transitional.
Rich Text `.rtf`	yes	yes	Through the same engine as `.docx`. Headers and footers, notes, comments and tracked changes are not carried.
OpenDocument Text `.odt`	yes	yes	As `.rtf`.
HTML `.html` `.htm`	yes	yes	Headings, lists, tables, emphasis, links and pictures; not the page's styling.
Markdown `.md` `.markdown`	yes	no	Open only.
Plain text `.txt`	yes	yes	Tables are written as tab-separated rows; saving lists everything else plain text cannot hold: styles, lists, notes, pictures, headers and footers, formatting, tracked changes. Read as UTF-8; written as UTF-8.
Word 97-2003 document `.doc`, template `.dot`	yes	no	Read-only: save as `.docx`. Text, styles (headings stay headings), character and paragraph formatting, lists, tables (nested too, with merges, borders and shading), sections with page setup, columns, headers and footers, footnotes and endnotes, tracked insertions and deletions, bookmarks, hyperlinks, inline pictures and fields are read; page numbers, cross-references and tables of contents stay live. Comments, text boxes, floating pictures and drawings, and frames are not read yet, and the problems list names them. Encrypted files and Word 6/95 and older are refused with a message saying which they are.
PDF		export	File ▸ Export as PDF.

Methodox Formula

Format	Open	Save	Notes
Excel workbook `.xlsx`	yes	yes	The native format. Parts Formula does not model (themes, styles, charts, pivot caches, external links, printer settings and more) are written back unchanged, and an unedited sheet is written back as it was. Formulas Formula cannot fully read are kept verbatim rather than rewritten. Strict Office Open XML opens and is saved as Transitional.
Excel macro-enabled workbook `.xlsm`	yes	yes	Opens like any workbook. Saving as `.xlsm` writes the VBA project back byte for byte; the macros are never run, read or changed. Saving as `.xlsx` leaves the macros out, as Excel does, with a note saying so.
CSV `.csv`	yes	yes	See CSV below. Saving writes the first sheet's computed values and lists what CSV cannot hold.
PDF		export	File ▸ Export as PDF, the whole workbook or the active sheet.

What Excel does with Formula's own content: spills, LET and LAMBDA, tables, charts and pivot tables open in Excel as Excel's own. Functions only Formula has, such as SQL.VIEW, and a workbook's Lua and C# functions are kept in the file by Excel but show #NAME? there, or their last values.

Methodox Expo

Format	Open	Save	Notes
PowerPoint presentation `.pptx`	yes	yes	The native format. Saving writes into the package that was opened, so untouched parts come back byte for byte. A deck started in Expo saves as a complete `.pptx`. Strict Office Open XML opens and is saved as Transitional. The theme is rewritten on save, and changed master text styles are written so PowerPoint shows them.
PDF		export	File ▸ Export as PDF.
PNG, JPEG		export	File ▸ Export as Image.
SVG		export	File ▸ Export Slide as SVG, the current slide. Further slides, notes and transitions are not in the SVG, and the export says so.
Plain text `.txt`		yes	File ▸ Save As, plain text: each slide's text in order, one block per slide, with tables as tab-separated rows. Empty placeholders and speaker notes are left out.

Methodox Nu

Format	Open	Save	Notes
`.pptx`	yes	yes	Nu's own format for a drawing. A presentation opened in Nu is read as pages of shapes: placeholders become plain shapes and master backgrounds are not drawn, which the problems list says. Saving keeps the theme, masters, layouts and notes. Layers are kept in an extension PowerPoint ignores.
draw.io `.drawio` `.dio`	yes	yes	Shapes, connectors with their glued ends, formatted labels (written back as draw.io writes them), layers and pages. Stencil shapes are drawn from draw.io's own libraries when they are on the computer, and as labelled boxes otherwise; either way they go back as the stencil. Every style draw.io gave a shape is kept and written back, and the problems list counts what was approximated.
LibreOffice Draw `.odg`	yes	no	Read-only: save as `.drawio` or `.pptx`. Shapes, formatted text, connectors glued to shapes, common geometry and styles, and pages.
Visio `.vsdx` `.vsdm`	yes	no	Read-only, as `.odg`; masters and style sheets are resolved. Gradients, sheared shapes, embedded objects and pictures Nu cannot draw are listed in the problems list.
draw.io in a picture `.drawio.png`	yes	no	The diagram inside the PNG opens; a plain PNG is a picture, placed with Insert ▸ Image.
SVG `.svg`	yes	current page	Opens as shapes you can edit; a `.drawio.svg` opens as its diagram. Saving writes the current page.
PDF, PNG, JPEG		export	File ▸ Export as PDF and Export as Image.

Methodox Office Math

Format	Open	Save	Notes
MathML `.mml`	yes	yes	Written with the StarMath commands inside it, which Math reads back first, so reopening gives exactly what was typed.
StarMath `.smf` `.txt`	yes	yes	The commands as plain text; nothing is lost either way.
PDF, PNG, JPEG		export	File ▸ Export as PDF and Export as Image.

Methodox Office content inside Office files

Documents that carry code or computed content stay .docx, .xlsx and .pptx. Methodox Office keeps what Office has no place for in a custom XML part of the package, a mechanism Office itself provides and preserves:

Scripts and smart objects: a part whose root is <project xmlns="https://schemas.methodox.com/office/2026/project">, holding a workbook's Lua and C# functions and a document's smart object bindings, every script and Divooka graph, the Document Parameters and what data-source Functions last fetched. Each smart object's value is ordinary text or an ordinary table in the document, inside a Word content control, so Word, LibreOffice and PDF show the last values, and Word keeps the controls and the part through its own saves.
Saved SQL queries in Formula: a part whose root is <sqlViews xmlns="http://schemas.methodox.io/formula/2026/sql-views">. Excel keeps it when it saves the workbook.

Opening a document never runs its code; see trust.

CSV

Reading: the encoding is detected from the bytes: a byte-order mark if there is one, otherwise UTF-8 when the file is valid UTF-8 and Windows-1252 when it is not, which the problems list mentions. Fields in quotes may contain commas, quotes (doubled) and line breaks. A field that reads as a number becomes a number; anything else stays text, so 3/4 and 50% stay text as LibreOffice reads them. The separator is the comma.
Writing: the first sheet's computed values, comma-separated, quoted where needed, UTF-8 without a byte-order mark; an error is written as Excel writes it (#DIV/0!, #N/A). Formulas, further sheets, merged cells, formatting, notes, filters, names and validation are left out, and the problems list names each.