CSV and JSON workflow guides
Carefully scoped tutorials about real import/export problems, including examples and limitations. Each guide links directly to a working browser tool. No account is required.
Step-by-step tutorials
Remove Duplicate Emails from a CSV (Keep the First Row)
Deduplicate a CSV mailing list by the email column, preserve the first matching record, and avoid deleting unrelated rows.
Read the walkthrough ›Convert JSON to CSV Without Losing Leading Zeros
Move JSON API records into CSV while understanding field unions, missing values, long identifiers and spreadsheet import behavior.
Read the walkthrough ›Our approach
We explain the exact behavior of each tool rather than promise an automatic fix for every dataset. Always back up your original export, choose the right comparison or conversion rules, and check the resulting file.
CSV conversion has genuine limitations: there are no native field types, spreadsheets can infer number formats, and a key like email is not always a unique business record identifier. These guides make the tradeoffs explicit before you process valuable data.
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