JWT Decoder
Decode JWT header and payload, inspect all claims, and check token expiry instantly.
Free Developer Tools
JSON, XML, API, regex, JWT, SQL, code formatting & debugging tools — all browser-based, no installation required.
Available Developer Tools
JWT Decoder Pro
Advanced JWT decoder with signature verification (HS256, HS512, RS256, RS512), expiry analysis, and claims extraction. Verify token authenticity with HMAC and RSA algorithms.
HTTP Status Code Checker
Check HTTP status codes, redirect chains, and response headers for any website. Batch check up to 50 URLs. See response time, security status, and server info.
Regex Tester
Test regular expressions live against any string. See matches, groups, and index positions.
JSON Formatter
Beautify and minify JSON instantly. Validates syntax and formats with 2 or 4-space indentation.
JSON to CSV Converter
Convert JSON arrays to CSV format instantly. Browser-based, no upload required.
CSV to JSON Converter
Convert CSV files into JSON format instantly. Browser-based, no upload required.
JSON to XML Converter
Convert JSON objects and arrays to properly structured XML. Browser-based, no upload required.
XML to JSON Converter
Convert XML documents to clean JSON format. Browser-based, no upload required.
XML Formatter & Validator
Format, beautify, and validate XML online free. Pretty-print or minify XML instantly. Browser-based — no data sent to a server.
Base64 Encoder / Decoder
Encode text to Base64 or decode Base64 back to plain text. Instant, browser-based — no data sent to a server.
URL Encoder / Decoder
Encode and decode URL strings with percent-encoding. Instant, browser-based — no data sent to a server.
Hash Generator
Generate MD5, SHA-1, SHA-256, SHA-384, and SHA-512 hashes from text or any file. Browser-based — no data sent to a server.
API Client
Send HTTP requests with Bearer, Basic Auth, or API Key authentication. Includes a headers editor, request body composer, and persistent history of your last 25 requests.
REST API Tester
Test REST APIs directly in your browser. Send HTTP requests with custom headers and body. View status, response headers, and JSON body instantly. No signup required.
cURL Command Generator
Generate cURL commands from a URL, HTTP method, headers, and request body. Supports GET, POST, PUT, PATCH, DELETE. Copy in one click.
SSL Certificate Checker
Verify any domain's SSL certificate instantly — validity, expiry date, issuer, SANs, TLS protocol, and SHA-256 fingerprint. Supports custom ports.
Number Base Converter
Convert numbers between binary, octal, decimal, hex, and any base from 2 to 36. Supports 0b/0x/0o prefixes, nibble grouping, and exact BigInt arithmetic.
UUID / GUID Generator
Generate RFC 4122-compliant UUID v4 (random) or UUID v1 (timestamp) identifiers. Bulk-generate up to 100 at once. No signup, browser-based.
Unix Timestamp Converter
Convert Unix timestamps to human-readable dates or any date to a Unix timestamp. Supports seconds and milliseconds. Shows UTC, ISO 8601, and local time.
...and 23 more developer tools
Developer Tools FAQ
Do you need API keys or credentials?
No. Most tools work directly in your browser without API keys. Some tools like REST API Tester may require you to provide the target API endpoint.
Is my code/data private?
Yes. All processing happens locally in your browser. Your code, API requests, and data never leave your device.
Can I use these for production?
Yes. These are reliable tools for testing and debugging. They use standard libraries and algorithms.