Free CLI Tool Validates Shopify Product CSVs Before Import to Catch Silent Errors

A command-line tool called Shopify CSV Preflight Validator allows merchants and developers to check product CSV files for errors before uploading them to Shopify. The tool runs locally without requiring any login or third-party data upload, scanning for common issues such as UTF-8 BOM characters, incorrect header casing, missing parent handles, duplicate handles, and invalid pricing. It produces three outputs: a corrected CSV file, a machine-readable errors list, and a human-readable markdown report. Two categories of unambiguous errors — BOM at file start and header case mismatches — are automatically fixed, while all other issues are flagged for the user to resolve manually. The tool is aimed at solo merchants handling bulk product updates as well as agencies managing client store imports.