JSON Tools
Format, validate, diff, minify, query, and convert JSON — all in your browser. No upload, no tracking, no server round-trip.
6 tools in this category
JSON Diff
Compare two JSON documents and see added, removed, and changed fields — privately.
JSON Escape / Unescape
Escape and unescape JSON strings in your browser — privately.
JSON Formatter
Format, validate, and minify JSON in your browser — privately.
JSON Minifier
Compress JSON for production — strip whitespace, comments, and trailing commas.
JSONPath Evaluator
Query JSON documents with JSONPath expressions — privately, in your browser.
JSON ↔ YAML Converter
Convert JSON to YAML and YAML to JSON in your browser — privately.
JSON is the lingua franca of modern APIs, configuration files, and log pipelines. These tools let you inspect, transform, and debug JSON without leaving the browser. Every byte stays on your device — we never proxy your data through a server, which matters when you are pasting a production payload that might contain secrets, customer PII, or internal identifiers.
When to use each JSON tool
Reach for JSON Format when a payload arrives minified and you need to read it. JSON Minify is the inverse — strip whitespace and optionally sort keys for deterministic diffs. JSON Diff surfaces additions, deletions, and changes between two documents with nested-path awareness. JSON Path lets you query a structure the way jq does in a terminal, but without installing anything. JSON Escape wraps a string so it is safe to embed inside another JSON document — useful when debugging nested API payloads. JSON to YAML gives you a human-readable version for pull requests and issue comments.
Privacy considerations
Developer tools that accept JSON are a well-known data-exfiltration risk: the input is often sensitive, and many online formatters silently log it. Every tool on this page runs entirely in the browser via JavaScript. You can verify this by opening the Network tab in your DevTools — there are no outbound requests during use. For extra peace of mind, you can disconnect from the internet after loading the page and every tool still works.
Performance
All JSON tools here are built on the browser's native JSON.parse and JSON.stringify, which are implemented in C++ inside V8 and SpiderMonkey. We do not ship a handwritten parser, so you get close-to-native speed even on documents that span a few megabytes. The 10MB browser tab limit is the practical ceiling; beyond that you want a streaming parser (clarinet, oboe) or a CLI tool.
Frequently asked questions
Is my JSON uploaded anywhere?
No. Every JSON tool here runs fully client-side in your browser via JavaScript. There is no server round-trip, no analytics payload containing your data, and no logging. You can verify with your browser's Network tab.
What is the largest JSON document I can paste?
Practically, browsers handle a few megabytes comfortably. Above ~10MB you may hit tab-freeze during `JSON.parse`. For larger documents, use a streaming parser or process the file server-side.
Do these tools support JSON5 or JSONC?
JSON Minify accepts JSONC (JSON with comments). JSON Format follows strict RFC 8259. JSON5 and trailing commas are on the roadmap but not yet shipped.
Why does JSON Diff show a different number of changes than `diff`?
JSON Diff is structure-aware: it matches object keys regardless of property order, so `{a:1,b:2}` and `{b:2,a:1}` are equal. A line-based `diff` would report them as different. This is usually what you want, but to compare raw text use the generic Text Diff tool instead.