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JSONL to CSV Converter

Paste or upload a JSONL file to convert it to a clean, spreadsheet-ready CSV. Headers are auto-detected from all keys found across every line.

Options
CSV Output

CSV output will appear here

Converting JSONL to CSV

JSONL to CSV conversion is a common step in data pipelines when you need to load JSON Lines data into a spreadsheet, SQL database, or BI tool. This converter scans all lines first to collect every unique top-level key, then uses those as column headers, filling empty cells with blank strings when a key is absent from a particular line.

Flatten Nested Objects

When you enable Flatten nested objects, nested keys are promoted to the top level using dot notation. For example, {"user":{"name":"Alice","id":1}} becomes two columns: user.name and user.id. Arrays are serialised as JSON strings in their respective cell.

Delimiter Options

Comma is the universal default, but semicolons are common in European locales where commas are used as decimal separators. Tab-separated values (TSV) avoid quoting issues entirely and are supported by Excel and Google Sheets via paste-and-split.

How It Handles Missing Fields

If one JSONL line has a key that others do not, the tool inserts an empty string in that column for every row where the key is absent. This ensures your CSV always has rectangular shape — the same number of columns in every row.