Int64 and exact decimals
IDs beyond 2^53 survive paste → view → edit → copy → download with every digit intact. Nothing is coerced to a float, ever.
jsonloupe
local-first · no backend, no telemetry
A loupe for JSON that is too big — and too precise — for your viewer.
Five-million-element arrays open instantly. Int64 IDs and exact decimals survive paste → edit → copy without a single rounded digit. Diff, query, decode Zstd payloads, export CSV — all inside your browser tab.
0 bytes uploaded · no account · MIT
Paste JSON
paste and it opens · nothing leaves this tab
⌃↵ to open
Built for the payloads that break other viewers
Five million elements, instantly
Virtualized tree with chunked expansion — [0 … 9999] range rows — and parsing, diffing, search and compression all off the UI thread.
Compressed input is first-class
Raw .zst, Base64-Zstd, or PostgreSQL \x… bytea is detected, decoded in the worker, and opened with a transformation trace.
Semantic side-by-side compare
Arrays align by identity, so reordering does not drown you in false changes. Ignore noisy fields by key or path prefix.
Paths, lenses, and “same value”
Copy any node as JSONPath, JSON Pointer, or JS accessor. Epoch → local date, lat/lng, uuid flags, and byte weight on collapsed nodes.
Tables and RFC 4180 CSV
Any array becomes a sortable table; export the table or a query result as exact-digit CSV in the current sort order.
A query language, not a search box
Filter, pluck, group and count across the whole document — evaluated in the worker, never on the main thread.
$.tasks[?(@.status == 'FAILED')]
| group(@.failureReason)
| count()
Diff that understands identity
Align arrays by id, a composite key, or automatic detection — then read what actually changed instead of a wall of index shifts.
~ changed 37
+ added 12
− removed 4
⇅ reordered 5
Your documents never leave your machine
Parsing, diffing and querying run in a web worker; documents are stored in IndexedDB on your own disk. There is no server to send them to. Ask — the optional English-to-query feature — stays off until you add your own API key, and even then it sends only the document's shape: field names and types, never values, shown to you in full before anything is sent.
fetch calls in app3 · all opt-in Ask
telemetrynone
licenseMIT
typescriptstrict
Payload tools
JSON, raw Zstd, PostgreSQL bytea, SQL cells, and standard or URL-safe Base64encode · JSON → Zstd → Base64
decode · payload → JSON
sent to model
Semantic compare