Free Spreadsheet & Data Tools — Clean CSV, Merge Excel, Format JSON

Split columns, merge fields, remove duplicates, trim whitespace

Convert CSV files to formatted Excel workbooks

Export Excel sheets as clean CSV files

Combine multiple Excel files or sheets into one workbook

Highlight differences, new rows, and missing data between two tables

Pretty-print and validate JSON data

Format and validate XML documents

Format, validate, and convert YAML files

Convert JSON arrays to downloadable CSV tables