Elite · v3
JSON Forge Elite
Enterprise JSON workbench for testers & engineers — format, validate, diff, decode JWTs, test APIs, search with regex, convert formats, and forensically inspect any JSON.
Formatter · Validator · Path Finder · Diff
API Tester · JSON↔CSV
JWT Decoder · Schema Validator
Regex Finder · Forensics · Base64 Media
100% client-side · zero uploads
9 tester tools · 1 interface
IBM Plex · GitHub-minimal UI
json-forge-elite — workspace.json
v3.0 STABLE
Raw Input
1
No JSON loaded
Paste JSON or load a sample above
Ctrl+Enter to parse
Ctrl+Enter to parse
Tree empty
Parse JSON to explore the node tree
Forensics ready
Parse valid JSON to see structural analysis & heatmap
No media detected
PNG, JPEG, GIF, WebP base64 strings will render here
JSON Schema
Validation Results
Schema Validator
Paste a JSON Schema on the left and data in the Editor, then click Validate. Checks types, required fields, min/max, minLength, pattern, enum & more.
JWT Token
Decoded client-side — no data leaves your browser
JWT Decoder
Paste any JWT above. Header and payload are decoded from base64url. Expiry, iat, and nbf are annotated with human dates and validity badges.
JSON Data
Regex Pattern Finder
Enter a pattern above. Searches all string values recursively through your JSON. Presets include email, URL, UUID, ISO date, IPv4, JWT, phone, hex colour & more.
Input
Output
JSON ↔ CSV Converter
JSON arrays → downloadable CSV, and CSV → JSON arrays. Handles quoted fields, special chars, and nested objects.
⚠ Browser CORS policy applies. JSONPlaceholder presets are CORS-enabled and work out of the box.
Request BodyPOST / PUT / PATCH
Headers
API Response Tester
Enter a URL and click Send. The JSON response is auto-parsed, pretty-printed, and available in the Editor for further analysis.
Try:
Try:
jsonplaceholder.typicode.com/users
Full Forensics Report
Forensics Report
Parse JSON in the Editor tab first. This view shows the full structural report: metrics, type distribution, key frequency heatmap, deepest paths, and base64 media detection.
JSON Forge Elite v3 — 9-Tool Workbench for QA & Developers
Format, validate, decode JWTs, test APIs, search regex, convert formats, forensics
The Professional JSON Toolkit Built for Testers
JSON Forge Elite v3 replaces five browser tabs with one unified interface. Format and validate JSON, decode JWT tokens, validate against JSON Schema draft-07, run regex searches across all string values, convert between JSON and CSV, fire live API requests, and run deep forensic analysis — all inside your browser, zero data transmitted.
All 9 Tools
What each tool does for testers
JSON Formatter & Validator
Real-time format, indent, and validate. Ctrl+Enter to parse. Pinpoint error messages with exact token position.
JSON Schema Validator
Validate any JSON against JSON Schema draft-07. Checks types, required fields, min/max, minLength, pattern, enum, and format.
JWT Decoder
Decode any JWT. Header and payload rendered as annotated claim rows. exp, iat, nbf validated with human-readable dates.
Regex Pattern Finder
Search all string values with any regex. Presets for email, URL, UUID, ISO date, IPv4, phone, JWT, base64, hex colour, semver.
JSON ↔ CSV Converter
Convert JSON arrays to downloadable CSV and parse CSV back to JSON. Handles nested objects, quoted fields, special chars.
API Response Tester
Fire GET/POST/PUT/PATCH/DELETE requests. JSON response auto-parsed and loaded into the editor for analysis.
Interactive Path Finder
Collapsible tree. Hover any node to see exact JSONPath notation live. One-click copy for use in code or queries.
LCS Diff Engine
Side-by-side JSON comparison using Longest Common Subsequence. Green for additions, red for removals. API regression ready.
Forensics & Heatmap
Full structural report: metrics, type distribution, key frequency heatmap, deepest leaf paths, null analysis, base64 media detection.
v3 vs v2 — What's New
| Feature | v3 Elite | v2 |
|---|---|---|
| JSON Formatter & Validator | ✓ | ✓ |
| Path Finder Tree | ✓ | ✓ |
| LCS Diff Engine | ✓ | ✓ |
| Base64 Media Detection | ✓ | ✓ |
| Sort Keys alphabetically | ✓ New | ✗ |
| JSON Schema Validator | ✓ New | ✗ |
| JWT Token Decoder | ✓ New | ✗ |
| Regex Pattern Finder + Presets | ✓ New | ✗ |
| JSON ↔ CSV Converter | ✓ New | ✗ |
| API Response Tester | ✓ New | ✗ |
| Key Frequency Heatmap | ✓ New | ✗ |
| GitHub-minimal Page Header | ✓ New | ✗ |
Frequently Asked Questions
What is the JSON Schema Validator and how does it work?
Paste a JSON Schema (draft-07) on the left pane of the Schema tab, ensure your data is in the Editor tab, then click Validate. The tool checks required properties, type conformance, minimum/maximum, minLength/maxLength, pattern regex, and enum constraints. Results are shown as green passes, amber warnings, and red failures, each with the exact path that violated the rule.
Can I verify a JWT signature with this tool?
The JWT Decoder decodes the header and payload from base64url encoding — entirely in your browser, zero network calls. Signature verification requires the secret key and is a server-side operation. The decoder annotates exp (expiry with human date and valid/expired badge), iat, nbf, sub, iss, aud, and jti claims automatically.
What regex presets are available?
Email address, HTTP/HTTPS URL, UUID v4, ISO 8601 date, IPv4 address, international phone number, JWT token pattern, base64 string, hex colour code, and semantic version. The finder searches all string values recursively through your entire JSON and highlights matches inline.
Does the API Tester support CORS?
The API Tester uses the browser's native Fetch API, so standard browser CORS policy applies. The JSONPlaceholder presets (typicode.com) are CORS-enabled and work out of the box as a demo. For internal APIs without CORS headers, you may need to run the tool locally or use a CORS proxy. The response is automatically parsed, pretty-printed, and loaded into the editor.
What does the JSON ↔ CSV converter support?
JSON to CSV conversion expects a JSON array of objects and outputs RFC 4180 compliant CSV. Nested objects are serialised as JSON strings in their cell. CSV to JSON parses the first row as headers and produces a clean JSON array. Both outputs can be downloaded as files.
What is the key frequency heatmap?
The heatmap in the Forensics tab visualises how frequently each unique key appears across your entire JSON structure. Keys that appear many times are shown with a darker, more saturated blue cell — making it easy to identify dominant schema fields, detect naming inconsistencies, or spot frequency anomalies in API responses.
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