xlsxslim 2.0.2

Reduce Excel file size by removing empty rows, columns, and excess formatting

xlsxslim

Reduce Excel file size by removing empty rows, columns, and excess formatting.

🇺🇦 Документація українською

v2.0.2 uses direct XML/regex manipulation — works with files of any size without memory issues.

Features

• 🚀 Memory efficient — processes 100+ MB files with < 100 MB RAM
• 📊 Direct XML — no openpyxl dependency for processing
• 📁 Auto-detect — finds single xlsx in current directory
• 💾 Safe — creates _slim copy by default

Installation

pip install xlsxslim

Quick Start

# Auto-detect single xlsx in current directory
xlsxslim

# Optimize specific file
xlsxslim report.xlsx

# Analyze only (dry run)
xlsxslim report.xlsx --dry-run

# Overwrite original file
xlsxslim report.xlsx --inplace

Example Output

xlsxslim v2.0.0

Input:  report.xlsx (68.64 MB)
Memory:  45.00 MB used, 16.00 GB available

Analyzing...

Sheets: 2

Sheet "Data":
  Used range:  A1:J1047716 → A1:I82
  Rows:        1,047,716 → 82 (-1,047,634)
  Columns:     10 → 9 (-1)

Sheet "Summary":
  Used range:  A1:K1047713 → A1:K76
  Rows:        1,047,713 → 76 (-1,047,637)

Optimizing...

Output: report_slim.xlsx (156.00 KB)
Saved:  68.49 MB (99.8%)
Memory:  48.00 MB used, 16.00 GB available

Options

Option	Short	Description
--output FILE	-o	Custom output path
--inplace	-i	Overwrite original file
--dry-run	-n	Analyze only, don't save
--verbose	-v	Detailed output
--quiet	-q	Minimal output
--suffix TEXT	-s	Output suffix (default: _slim)
--version		Show version
--help	-h	Show help

How It Works

xlsx files are ZIP archives containing XML. xlsxslim:

1. Analyzes — Scans XML to find actual data bounds
2. Removes — Strips rows/columns/cells beyond data range
3. Rebuilds — Creates new ZIP with optimized XML

No need to load entire workbook into memory.

Why Files Get Bloated

Excel tracks a "used range" that includes any cell ever formatted:

• Ctrl+Shift+End → format applied to row 1,048,576
• Copy-paste brings invisible formatting
• Conditional formatting on entire columns
• Deleted data leaves formatted empty cells

v2.0 vs v1.x

Feature	v1.x (openpyxl)	v2.0 (XML)
68 MB file	46+ GB RAM, crashes	< 100 MB RAM
Speed	Slow	Fast
Dependencies	openpyxl	None (stdlib)

Exit Codes

Code	Description
0	Success
1	File not found
2	Multiple files (specify explicitly)
3	Read/write error
4	Already optimized

Testing

# Install dev dependencies (includes openpyxl for creating test fixtures)
pip install -r requirements-dev.txt

# Run tests
pytest

# Run with verbose output
pytest -v

License

BSD 3-Clause License

Copyright

Copyright (c) 2025, Vladyslav V. Prodan

Contact

• GitHub: github.com/click0
• Phone: [phone]