Convert NDJSON to JSON Online
Convert NDJSON files to JSON format directly in your browser. No upload required — your data never leaves your device.
About this conversion
This tool converts NDJSON files to JSON format directly in your browser — no account required, no file upload, no waiting for a server. It processes your data entirely within your browser using WebAssembly, so nothing ever leaves your device.
The tool preserves all columns and data types from your source file and writes a valid JSON file ready to download. Large files are handled efficiently using a vectorised columnar engine.
Not sure which format you need? Read our JSON vs NDJSON comparison for a side-by-side breakdown.
Frequently Asked Questions
What is JSON format?
JSON (JavaScript Object Notation) is a lightweight, human-readable format that supports nested structures, making it ideal for APIs and document-oriented data.
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 JSON?
Both NDJSON and JSON are common data formats used in engineering and analytics workflows.
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