Try it — your file never leaves this tab
Why another JSON viewer?
In 2026 the widely-used JSON Formatter Chrome extension was sold and turned into adware — injecting tracking scripts into pages. Trust in "handy JSON tools" collapsed overnight.
PrivJSON is different by construction:
Zero network requests after load — verify in DevTools › Network.
Single HTML file — save it, run it offline forever.
~1300 readable lines — no build step, no dependencies, audit it in one coffee break.
Lossless integers — numbers beyond 2^53 stay exact, never silently rounded.
🧵 Parsing off the main thread
A Web Worker reads and parses your file in the background. UI heartbeats continue during parsing — the page stays responsive.
🔒 Private by architecture
Not "we respect your privacy" — there is no upload path at all. Close the tab, data is gone. Works fully offline.
🔎 Search that covers everything
Worker-side, interruptible search across the entire dataset (not just rendered rows), with JSONPath results and path-copy mode.
Honest limitations
• Parsing loads the file into memory as text first; a 100 MB file wants a browser tab with ~1 GB free memory. No incremental/streaming parser in this version.
• Tree children render up to 200 per node (lazy-loaded from the worker); deep search caps at 8M visited nodes or 5 s per query and says so when capped.