What's preserved structurally
Multi-level numbering (1, 1.1, 1.1.2) is preserved as ordered list nesting in Markdown — clauses keep their identifiers, so a reference to "Section 4.2(b)" still points to the same place after conversion. Defined terms (capitalised in the original) stay capitalised. Party names, dates, addresses, monetary amounts, governing law — all preserved verbatim. Signature blocks are preserved as plain text (they're not actually executable in Markdown form, but the structure is visible).
What's lost or simplified
Page-level layout (where a clause appears on which page) is gone — Markdown is flow-based. Table of authorities and TOC are not regenerated (the headings remain so any tooling can rebuild a TOC). Exhibits and schedules in the same .docx are concatenated as appendix sections; if they were separate files, they need separate conversions.
Honest legal disclaimer
The Markdown output is a faithful content extraction, suitable for search, AI analysis, clause libraries, redlining workflows, and internal document management. It is not a court-admissible record of the original executed contract. For evidentiary purposes, the original signed .docx (or PDF of the signed copy) is what matters. Use this tool for working with contract content, not for replacing the executed original. If you also have signed PDF versions, see PDF to Markdown for those.