Convert NDJSON to CSV Online
Convert NDJSON files to CSV format directly in your browser. No upload required — your data never leaves your device.
About this conversion
NDJSON (Newline-Delimited JSON) is the standard format for log data, event streams, and incremental database exports — but it is not directly usable in spreadsheets, SQL databases, or most analytics tools without conversion. Converting NDJSON to CSV flattens your records into a tabular format that works everywhere, making it the essential first step for analysing log data, streaming exports, or event archives.
Common use cases include converting server access logs for analysis in Excel or a database, transforming a bulk Elasticsearch export into CSV for reporting, processing event stream snapshots, loading incremental database change-data-capture exports into a staging table, and converting application log files emitted by frameworks like Pino, Bunyan, or Loguru.
If your NDJSON records contain nested objects, this tool serialises those nested fields as JSON strings in the CSV output. For a cleaner flat table, run the resulting CSV through the Flatten tool to expand nested keys into their own columns using dot notation. All NDJSON records should share the same top-level key structure for the column schema to be consistent across rows.
Not sure which format you need? Read our NDJSON vs CSV comparison for a side-by-side breakdown.
Frequently Asked Questions
What is CSV format?
CSV (Comma-Separated Values) is a plain-text tabular format supported by virtually every data tool, spreadsheet app, and programming language.
Is my NDJSON data private?
Yes — completely. Your file is never uploaded to any server. All conversion happens inside your browser using WebAssembly — locally, with no upload. Once you close the tab, nothing is retained.
What is the maximum file size?
The free limit is 50 MB. For larger files, performance depends on your device's available memory — most modern machines can handle 500 MB to 1 GB comfortably.
What is the difference between NDJSON and CSV?
NDJSON is ideal for streaming and append-only log data. CSV is better for tabular analysis in spreadsheets, databases, and analytics tools.
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