Practical guides for messy data.
Short, specific walkthroughs for the spreadsheet cleanup problems that eat your afternoon. Every guide shows the manual method and the fast one.
- 3 min read
How to Split a Large CSV File Into Smaller Ones
Split a big CSV by row count or by column value using split, Python, or a browser tool — and keep the header row on every part.
Read the guide → - 3 min read
How to Merge Multiple CSV Files Into One
Combine CSV files with the command line, Python, Power Query, or a browser tool — and handle the mismatched headers that break naive approaches.
Read the guide → - 4 min read
How to Fix Garbled Characters in a CSV (é Instead of é)
Why mojibake happens at the byte level, why it's exactly reversible, and how to fix it in Excel, Python, the command line, or your browser.
Read the guide → - 4 min read
How to Convert a CSV to SQL INSERT Statements
Generate INSERT statements from a CSV with Python or a browser tool — plus escaping, column types, and why COPY beats INSERT for large files.
Read the guide → - 4 min read
How to Convert CSV to JSON (And the Type Traps to Avoid)
Convert CSV to JSON with Python, JavaScript, jq, or a browser tool — plus the type-inference mistakes that silently destroy ZIP codes and IDs.
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How to Compare Two CSV Files and Find the Differences
Find added, removed, and changed rows between two CSV exports — with diff, Excel, Power Query, pandas, or a browser tool — and the row-matching decision that determines whether any of them work.
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How to Remove Duplicate Rows in Excel and CSV Files
Four ways to remove duplicate rows — Excel's built-in tool, Google Sheets formulas, Python, and a browser tool — plus why duplicates often survive the first attempt.
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How to Fix Mixed Date Formats in a CSV
When one column contains 03/14/2024, 14 Mar 2024, and 2024-03-14 at once — how to detect the mess, resolve the 01/02 ambiguity, and convert everything to one format.
Read the guide → - 4 min read
How to Split a Full Name Column into First and Last Name
Excel formulas, Flash Fill, Google Sheets, and Python for splitting name columns — plus the middle names, suffixes, and compound surnames that break naive approaches.
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