Searches like "compress xlsx file" and "shrink xlsx file size" come from teams sharing heavy workbooks with charts, formulas, and embedded assets.

Why Excel Files Stay Large

XLSX is a zipped container of XML parts. Redundant strings, styles, and worksheet data can still be optimized beyond default packaging.

Safe XLSX Compression Rules

Do not alter formulas or cell references
Preserve workbook relationships and metadata
Verify file opens cleanly in Excel after decompression

PZIP applies container-aware optimizations and keeps outputs byte-safe for operational use.

Check XLSX benchmark results and run a workbook test.