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Format and fidelity evidence

Word, Excel, and PowerPoint Format Compatibility

Check OfficeIMO support for DOC, DOCX, XLS, XLSX, XLSB, PPT, PPTX, templates, slide shows, macros, conversion directions, preservation, and fidelity.

3 Office families 28 file variants 137 tracked behaviors

OfficeIMO.Word

Microsoft Word

33 tracked behaviors

Legacy binary

.DOC.DOT

Modern

.DOCX.DOCM.DOTX.DOTM

DOC (Word 97–2003)

Legacy DOC import, writing, round-trip behavior, and DOC/DOCX conversion.

33 behaviors

Coverage is still incomplete. Rows marked “Not implemented” are explicit product gaps, not supported behavior.

Represent
Closest representation 3 Native 23 No destination equivalent 1 Opaque content 6
Read and import
Native 22 Not applicable 1 Not implemented 1 Preserved records 9
Create legacy
Editable approximation 12 Blocked 8 Native 10 Not applicable 2 Not implemented 1
Edit and round-trip
Native 10 Not applicable 1 Preserved records 22
Modern to legacy
Editable approximation 12 Blocked 7 Source retained 1 Native 9 Visual fallback 4
Legacy to modern
Blocked 1 Dropped with diagnostics 8 Source retained 1 Native 22 Not applicable 1
Explore OfficeIMO.Word Read the Microsoft Word guide Open the Microsoft Word API reference

OfficeIMO.Excel

Microsoft Excel

48 tracked behaviors

Legacy binary

.XLS.XLT.XLA.XLM.XLW

Modern

.XLSX.XLSM.XLTX.XLTM.XLAM.XLSB

XLS (BIFF8)

Legacy XLS workbook behavior and XLS/XLSX conversion.

28 behaviors

Coverage is still incomplete. Rows marked “Not implemented” are explicit product gaps, not supported behavior.

Represent
Closest representation 4 Native 19 Opaque content 5
Read and import
Native 19 Preserved records 9
Create legacy
Editable approximation 10 Blocked 8 Native 8 Not applicable 1 Not implemented 1
Edit and round-trip
Native 8 Preserved records 20
Modern to legacy
Editable approximation 10 Blocked 5 Source retained 1 Native 8 Visual fallback 4
Legacy to modern
Editable approximation 1 Dropped with diagnostics 7 Source retained 1 Native 19

XLSB (binary Open XML)

Binary workbook lifecycle, preservation, and XLSB/XLSX conversion.

20 behaviors
Represent
Closest representation 3 Native 12 Opaque content 5
Read and import
Native 12 Preserved records 8
Create XLSB
Editable approximation 3 Blocked 7 Native 9 Not applicable 1
Edit and round-trip
Preserved records 20
XLSX to XLSB
Editable approximation 3 Blocked 4 Source retained 1 Native 9 Visual fallback 3
XLSB to XLSX
Dropped with diagnostics 4 Source retained 4 Native 12
Explore OfficeIMO.Excel Read the Microsoft Excel guide Open the Microsoft Excel API reference

OfficeIMO.PowerPoint

Microsoft PowerPoint

56 tracked behaviors

Legacy binary

.PPT.POT.PPS.PPA

Modern

.PPTX.PPTM.POTX.POTM.PPSX.PPSM.PPAM

PPT (PowerPoint 97–2003)

Legacy PPT import, writing, round-trip behavior, and PPT/PPTX conversion.

56 behaviors
Represent
Closest representation 3 Native 41 No destination equivalent 4 Opaque content 8
Read and import
Blocked 4 Native 44 Preserved records 8
Create legacy
Editable approximation 2 Blocked 10 Native 43 Not applicable 1
Edit and round-trip
Blocked 4 Native 18 Preserved records 34
Modern to legacy
Editable approximation 2 Blocked 22 Source retained 1 Native 29 Visual fallback 2
Legacy to modern
Blocked 4 Dropped with diagnostics 8 Source retained 1 Native 43
Explore OfficeIMO.PowerPoint Read the Microsoft PowerPoint guide Open the Microsoft PowerPoint API reference

What the states mean

Compatibility is an outcome, not a badge.

OfficeIMO reports whether content remains native and editable, becomes an approximation or visual fallback, is preserved for recovery, or is blocked to prevent silent loss.

NativeRepresented directly in the destination format.
Editable approximationRetained as editable content with a documented approximation.
Closest representationMapped to the closest supported representation, with a reported fidelity difference.
Visual fallbackAppearance retained as a static image when editability is unavailable.
Preserved recordsOriginal records retained without claiming full editing semantics.
Opaque contentContent carried without interpreting its internal feature semantics.
Source retainedOriginal source embedded with hash verification for recovery.
BlockedOperation refused when proceeding would silently misrepresent the result.
Not applicableThe operation does not apply to this feature or format direction.
Not implementedThe contract explicitly records a path that is not implemented yet.
No destination equivalentThe destination format has no representation for this feature.
Dropped with diagnosticsThe feature is omitted and reported as known loss.

Choose the result your workflow needs

The safest conversion is not always the one that produces a file at any cost. OfficeIMO lets an application choose whether it requires native representation, accepts an editable approximation, prefers visual fidelity, permits a documented best-effort result, or retains the complete source for recovery.

Use AnalyzeConversion(...) before writing when a service needs an approval gate. The returned report identifies the affected feature, source location when available, chosen fallback, and fidelity dimensions at risk. RequireNoLoss() turns any known loss or blocked feature into a failed operation.

Evidence is grouped by concrete format contract. Excel XLS and XLSB have separate rows and counts because BIFF8 and binary Open XML do not share the same implementation or fidelity boundary.

Important boundaries

  • A listed extension means OfficeIMO can classify and route the format. It does not mean every format is a writable destination.
  • Legacy Excel .xlt, .xla, .xlm, and .xlw authoring and PowerPoint .ppa authoring are currently blocked by structured preflight.
  • Visual fallbacks preserve appearance but are not presented as editable formulas, charts, SmartArt, or document structure.
  • Embedded source payloads may contain macros, linked content, or other active material. Treat recovered bytes as untrusted input.
  • External LibreOffice and optional Microsoft Office checks are validation oracles, not runtime dependencies.

Read the compatibility contract and validation guide for the complete generated rows, corpus policy, and interoperability gates.