Open and reshape huge JSON files¶
jsonreshape is a free, open-source desktop app and command-line tool for JSON and JSON Lines (NDJSON) files that are too large to open in a normal editor — from 100 MB to several gigabytes.
A 2.1 GB file with 6.5 million records. The clock under the window is real time; only the filter is played 8× faster, and the strip says so.
Why it is different¶
- Nothing is loaded into memory as a whole. A multi-gigabyte file is indexed once (the byte boundaries of every record), then only the records you look at are read. A 2 GB file is ready in about 3 seconds; 10 million records sort in 77 seconds using under 400 MB of RAM.
- The original file is never changed. Edits live in a separate layer; saving atomically
replaces the file, keeping a
.bakbackup by default. - Offline and private. No telemetry and no network access — your data never leaves your machine.
- Fast core, friendly tools. A Rust core with a pure-Python fallback, a PySide6 desktop window, and a scriptable CLI.
What you can do¶
| Task | Guide |
|---|---|
| Open and browse a 2–5 GB JSON / JSON Lines file | Open a large JSON file |
| Convert to CSV, Excel, SQLite, Parquet or Feather | Convert JSON |
| Compare two JSON files | Compare JSON files |
| Repair an invalid / broken JSON file | Repair broken JSON |
| Flatten nested JSON into a table | Flatten nested JSON |
| Split one big file / merge many files | Split and merge JSON |
Also included: full-text and regex search, a filter language, multi-key sort, field statistics with histograms, duplicate detection, JSON Schema generation and validation, and a drag-and-drop structure builder. See the CLI reference and the Python API.
Install in one line¶
From the first release on:
pip install jsonreshape # CLI + Python library
pip install "jsonreshape[gui]" # add the desktop window
See Installation for prebuilt Windows binaries, building from source, and the optional Parquet / import extras.