macOS · iPadOS · iOS
Open the 2 GB JSON. Query it. Fix it.
JSON Scope opens the files other tools give up on. It maps the document, indexes it once, and stays interactive without ever loading it into memory. A 900 MB API dump, a 2 GB export, a multi-million-line log.
Everything happens on your device. No account, no network, nothing collected.
macOS 14.0 or later. iPadOS and iOS 17.0 or later. Universal Purchase.
The problem
Every other tool fails at the size that matters
Backend dumps, database extracts and ML datasets routinely run to hundreds of megabytes. That is precisely where the usual options stop working.
Desktop viewers run out of memory
Most load the whole document into a heap. One documents a 60 to 1 memory ratio, which puts a 500 MB file at 30 GB of RAM. In practice they cap out far below that.
Browser tools die well before a gigabyte
A web viewer has to parse the file into a JavaScript heap, and it has to receive the file first. For proprietary data, uploading it is not an option at all.
The command line gives you no way to look
jq streams happily, and then hands you a wall of text. There is no tree, no table, and no way to explore something whose shape you do not already know.
Free
A complete tool for everyday files
Free is not a demo. Files up to 50 MB, with the tree, the raw view, search, validation and Quick Look — no time limit and no nagging.
Files up to 50 MB
Comfortably above every ordinary JSON file, so normal work is never interrupted by a prompt to buy something.
A virtualised tree
Expands lazily at any depth. A container with ten million children opens without stalling, and every row shows its type and child count.
The raw bytes
A byte view with correct line numbers for both Unix and Windows line endings. Select a node and the view reveals its exact span.
Find, with counts
Search keys and values incrementally over the stream, with match counts and next and previous navigation. Cancellable at any point.
Validation that tells you where
A syntax error reports the byte offset, the line, the column, the offending token and what was expected. Never a bare “invalid JSON”.
Quick Look in Finder
Press space on a .json file and read a formatted, syntax-coloured preview without opening anything.
Pro
Scale, and the power tools
Pro removes the size limit and adds the querying, reshaping and editing that turn a very large file into an answer.
Any size at all
ProTested against 2 GB fixtures. The file is streamed and indexed once, so resident memory stays flat no matter how large it gets.
Line-delimited logs
Pro.jsonl and .ndjson, including event logs with tens of millions of lines.
Records as rows
ProAn array of objects becomes a table with inferred columns. Types drive sorting and alignment, and ragged records leave empty cells rather than misaligned rows.
JSONPath and jq
ProWildcards, recursive descent, slices, unions and filters. Or the jq syntax you already know, evaluated lazily so a query never materialises the file.
Schema and diff
ProInfer a JSON Schema 2020-12 for any node to document an undocumented API, or compare two documents structurally, keyed for objects and positional for arrays.
Edits that preserve your file
ProChange a value and save. Every byte you did not touch is written back verbatim, so whitespace, key order and numeric literals survive exactly. The save is atomic.
In use
On iPhone and iPad
The same engine and the same views, laid out for the screen you are holding. These are captures of the running app on a 4,000-record document.
Open the 2 GB JSON.
Records as rows, types inferred.
JSONPath and jq, on the whole file.
The bytes as they really are.
Path, schema and edits for any node.
On iPad
Three panes on iPad.
The inspector, with room to breathe.
Privacy
It cannot phone home, and that is enforced by the system
No network entitlement
On macOS the app ships without the network-client entitlement, so the operating system itself prevents it from opening a connection. It is not a promise; it is a capability the app does not have.
No third-party code
Zero runtime dependencies. No analytics package, no crash-reporting SDK, nothing that could collect anything on someone else’s behalf.
No account, ever
There is no sign-in and nothing to create. The App Privacy label reads “Data Not Collected”, because that is what the privacy manifest declares.
Your files stay put
Documents are read where they already live and are never copied elsewhere. Erase all data clears every cached index, recent, bookmark and query in one action.
The full detail is in the privacy policy.
Pricing
Free to use. Pro when you need the scale.
One purchase covers macOS, iPadOS and iOS. Both subscriptions include a 7-day free trial, and there is a one-time option if you would rather not subscribe at all.
| Capability | Free | Pro |
|---|---|---|
| Opening files | ||
| Open .json files up to 50 MB | Included | Included |
| Open .json files of any sizeTested against 2 GB fixtures. Memory stays flat regardless of file size. | Not included | Included |
| Line-delimited .jsonl and .ndjsonIncluding files with tens of millions of lines. | Not included | Included |
| Reading and navigating | ||
| Virtualised tree view with lazy expansion | Included | Included |
| Raw byte view with line numbers | Included | Included |
| Find keys and values, with match counts | Included | Included |
| Validate with precise line and columnReports the offending token and what was expected, not just “invalid JSON”. | Included | Included |
| Format and minify | Included | Included |
| Copy JSONPath, value or subtree | Included | Included |
| Querying and shaping | ||
| Table view with inferred columns, sort and filterArrays of objects become rows. Types drive sorting and alignment. | Not included | Included |
| JSONPath queriesWildcards, recursive descent, slices, unions and filter expressions. | Not included | Included |
| jq-style queriesIdentity, fields, indexing, slices, iteration, pipes, select, object construction, keys, length, map and to_entries. | Not included | Included |
| JSON Schema 2020-12 inference | Not included | Included |
| Structural diff of two documents | Not included | Included |
| Editing and exporting | ||
| Edit values and keys, then saveEvery byte you did not touch is written back verbatim. Saving is atomic. | Not included | Included |
| Export any node as JSON or CSV | Not included | Included |
| System integration | ||
| Quick Look previews in FindermacOS only. | Included | Included |
| “Query JSON File” action for Shortcuts and Spotlight | Not included | Included |