JSON Viewer
Validate, pretty-print, and navigate JSON as a collapsible tree.
How to Use
- Paste or drop JSON content into the input area.
- The tree view appears in the right panel — click arrow icons to collapse or expand any node.
- Each value shows its type (string, number, boolean, null, array, object) and arrays/objects show their length.
- Use the search field to find keys or values across the entire structure.
- Errors show the failing line and column with a hint about what went wrong.
- Use 'Relaxed' mode to tolerate JSONC-style comments and trailing commas.
Notes
About the JSON Viewer
Whether you are at a desk or on your phone, the JSON Viewer makes image, audio and file tasks easy — and it is completely free. Validate, pretty-print, and navigate JSON as a collapsible tree.
How it works
Type in what you have, and the answer shows up right away. Change anything and it updates by itself. Everything runs in your browser, so it is fast and nothing you type is sent away.
Want the deeper story? The Knowledge Base explains the ideas behind the tools in more detail.
Frequently Asked Questions
What's the difference between this and the JSON Formatter?
JSON Formatter focuses on producing nicely-indented text output. JSON Viewer focuses on interactive exploration — collapsible tree, type display, search across the structure. Use Formatter when you want clean text to copy or commit; use Viewer when you want to navigate a large or complex JSON to understand it.
Will it handle large files?
Yes, up to several MB without trouble. Files above 10 MB are rendered with the first 2 levels expanded by default to avoid performance issues — you can drill into specific subtrees as needed. Multi-hundred-MB files are better explored with jq or a streaming parser.
Does it support JSON5 or JSONC?
Strict JSON by default. Use the 'Relaxed' toggle to strip // line comments, /* block comments */, and trailing commas before parsing — covers most JSONC and JSON5 cases. For full JSON5 (single-quoted strings, unquoted keys, hex numbers, etc.), use a dedicated JSON5 parser.
Can I edit the JSON in the viewer?
Edit in the input pane and the tree updates live. For node-by-node editing inside the tree (clicking a value to change it), use a dedicated JSON editor like jsoneditor.org. This tool is read-mostly with full re-edit on the source.
How does search work?
It searches both keys and values across the entire structure, expanding parent nodes to reveal matches. Useful for finding 'where did this field come from?' in deeply-nested API responses or large config files.
Is the JSON uploaded anywhere?
No. Parsing and tree rendering happen entirely in your browser. You can safely paste API responses with sensitive data, internal config, or production data — nothing leaves your machine.
How do I use the JSON Viewer?
Just type your numbers. The answer shows up right away — there is no button to press. Change anything and it updates by itself.
Is it free? Does it work without internet?
Yes to both. It is free with no sign-up, and once the page has loaded it keeps working even with no internet.
Where does my data go?
Nowhere — every calculation runs on your own device. Nothing you enter is uploaded, logged, or stored.
Common Use Cases
Exploring API responses
Paste a large API response and navigate the tree to find the specific field or pattern you need.
Debugging config files
package.json, tsconfig.json, .vscode/settings.json — see the full structure interactively.
Inspecting GraphQL responses
GraphQL responses can be deeply nested; tree view makes them tractable.
Validating before commit
Confirm a JSON file parses correctly before committing it to version control.
Schema discovery
Reverse-engineer a JSON schema by browsing structure and types.
Localization file review
Browse i18n translation JSON files (often deeply nested) to find missing or mistranslated keys.
Last updated: