Data Transformer
Explore, refine, filter and map CSV and JSON without uploading data to a server.
Bring in your data
Paste CSV or JSON, or drop a file. We detect CSV delimiters automatically and show a preview before you change anything.
Local processing: the file stays on your device
Data Transformer is a free tool for preparing CSV and JSON files without writing code. Remove empty rows and duplicates, trim values, rename columns, filter records, replace text and normalize dates. Everything runs in your browser and the result can be exported as CSV or JSON.