CSV knowledge base
Guides that solve real data problems
Use these practical workflows to clean messy exports, move data between formats, and prepare files for spreadsheets, CRMs, and databases.
Clean and repair data
- Find Fuzzy Duplicates in CSV Files
Find near-duplicate rows using similarity matching. Catch typos like 'Jon Smith' vs 'John Smith'. Free online tool.
- Anonymize CSV Data (GDPR/Testing)
How to mask sensitive data in CSV files. Anonymize names, emails, and phones for testing or GDPR compliance.
- How to Clean Email Lists Before Sending (5-Step Guide)
Clean your email list to improve deliverability and avoid spam complaints. Remove duplicates, validate formats, and fix common issues.
- Why Won't My CSV File Open in Excel? (7 Fixes)
Troubleshoot CSV files that won't open in Excel. Fix file associations, size limits, corruption, and encoding issues.
- Fix CSV Encoding Issues (UTF-8 Guide)
Fix weird characters in your CSV files. Understand UTF-8 vs ANSI, fix mojibake (), and ensure your data displays correctly everywhere.
- How to Clean CSV Data Without Losing Your Mind
Learn practical techniques to clean messy CSV files. Remove duplicates, fix formatting, and standardize data without Excel crashes or complex scripts.
Convert and export
- Convert CSV to HTML Table
Convert CSV files to HTML table code for websites. Free online tool with proper escaping and semantic markup.
- Convert CSV to Markdown Table
Convert CSV files to Markdown tables for GitHub README files, documentation, and blog posts. Free online tool.
- Convert TSV to CSV (Tab-Separated to Comma-Separated)
Convert TSV files to standard CSV format. Free online converter for tab-delimited data. Works with Excel exports.
- Batch Convert Multiple Excel Files to CSV
How to convert 100 Excel files to CSV at once. Use VBA macros, Python scripts, or batch converters to save hours of manual work.
- Best Free CSV Viewers for Mac & Windows
Excel isn't the only way to open CSVs. Check out the best free CSV viewers like Tad, Miller, and online tools for large files.
- Compare Two CSV Files (Find Differences)
How to compare two CSV files to find added, removed, or changed rows. Methods using Excel, command line, and diff tools.
Merge, split, and compare
- Combine CSV Files from Multiple Folders
How to merge CSV files scattered across different subfolders. Recursive merging using Command Line and Python.
- Compare Two CSV Files (Find Differences)
How to compare two CSV files to find added, removed, or changed rows. Methods using Excel, command line, and diff tools.
- CSV vs XLSX vs TXT: Which Format to Use?
Compare CSV, XLSX (Excel), and TXT formats. Understand the differences, file size, compatibility, and when to use each for your data.
- How to Combine Facebook Lead Reports (The Fast Way)
Merge multiple Facebook lead export files into one master list. Step-by-step guide for marketers dealing with monthly or campaign-based lead downloads.
- Merge CSV Files with Different Headers
How to combine CSV files that have different columns. Learn about union, intersection, and schema mapping to merge mismatched data.
- Merge CSV Files in Order by Date
How to merge multiple CSV files and ensure the final result is sorted chronologically. Avoid messy, unsorted data dumps.
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