Inspect large exports
Review the shape of database exports, API captures and generated datasets before processing them elsewhere.
100% local · files never leave your browser
View tool
Large JSON File Viewer
Open and inspect large JSON files locally in your browser. Explore structure and file statistics without uploading sensitive data.
✓ Free to use✓ No signup✓ Runs locally
160 bytes · local only
Waiting
♢
Processed entirely in this tab
Your input and result are not sent to JSON Hearth or stored on a server.
When to use it
What Large JSON Viewer helps you do
Use the large JSON viewer when a normal text editor becomes slow or when you need a quick structural overview before writing a script or query.
Find structural problems
Check nesting, arrays and value types when a downstream importer rejects a file.
Keep files local
Examine production-like data without sending the document to an application server.
How it works
Large JSON Viewer, without the upload.
Add your data
Paste a value, open a local file or begin with the working sample.
Run the tool
The transformation executes in your browser, not on our servers.
Review the result
Check the output, then copy or download it for your next task.
Important limitations
What to check before using the result
Review required
Maximum practical file size depends on the browser, device memory and document structure.
Review required
This viewer helps inspect data; it is not a replacement for a streaming database or command-line processor.
Common questions
About Large JSON Viewer
Does Large JSON File Viewer upload my data?
No. Your input is processed by code running in your browser and is not sent to an application server.
Is Large JSON Viewer free to use?
Yes. The tool is free, requires no account and can be used directly in the browser.
Can I view a large JSON file without uploading it?
Yes. The file is read by browser-side code and is not intentionally uploaded to JSON Hearth.
Why can two files of the same size behave differently?
Deep nesting, very large arrays and long strings can require different amounts of browser memory even when file sizes are similar.