Convert JSON Lines to Fixed Width

Convert your JSON Lines / NDJSON data to Fixed Width/Fixed Length quickly

Drop your JSON_LINES (.jsonl) file here (or click to browse).
(100 MB or less file)
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Convert JSON Lines to Fixed Width using an API
JSON Lines / NDJSON

JSON Lines (also known as NDJSON — Newline Delimited JSON) is a text format where each line is a self-contained, valid JSON value, typically a JSON object. It is widely used for streaming data, log files, and large data exports because files can be read and written one record at a time without loading the entire document into memory. Common file extensions are .jsonl and .ndjson.

Fixed Width/Fixed Length

A fixed width (or fixed length) file is a text data file in which each field in a record is allocated a specific number of characters, regardless of the actual content length. This consistent column width ensures that data aligns in columns across rows, making the file appear like a table when viewed in a plain text editor. If a field's content does not fill the entire width, it's padded with spaces or other placeholder characters. Fixed width files are often used in legacy systems, mainframes, and financial data processing systems.