Convert JSON to CSV and back — nested JSON flattened
Paste an array of JSON objects and get a CSV; paste CSV and get JSON. Nested objects flatten to dot-notation columns. It runs in your browser (0 uploads, works offline).
How to use it
- Paste your input into the left pane.
- Choose any options shown above the panes.
- The result updates live on the right — Copy or Download it.
FAQ
How do I convert JSON to CSV for free?
Paste a JSON array of objects and choose JSON → CSV — it flattens nested fields into dot-notation columns (addr.city) and produces RFC-4180 CSV in your browser, with no upload. Switch the direction to parse CSV back to JSON.
How is nested JSON handled?
Nested objects are flattened with dot-notation keys, so { addr: { city: "Pune" } } becomes a column named addr.city. Arrays are kept as a JSON string in the cell, which round-trips safely.
Are leading zeros preserved?
Yes — CSV values stay as text, so a PIN code like 0560001 keeps its leading zero when parsed back to JSON, rather than becoming a number.
Is my data uploaded?
No. Conversion runs locally and nothing is stored; it works offline.
Limits
Flattens nested objects; arrays become JSON strings in a cell. Deeply irregular JSON where objects have very different keys produces a wide, sparse CSV.
Related
CSV to Markdown makes a table for docs; CSV to SQL generates INSERT statements; the delimiter converter switches separators.
Bookmark this page (Ctrl+D, or ⌘D on Mac) or install the app — it works offline the next time you need it.