JSON and data conversion
Validate and beautify JSON, compare two documents, flatten nested objects into CSV, or convert between YAML and JSON.
Free Online Developer Tools
Format, compare and convert data without installing anything. These developer utilities run locally in your browser whenever possible, so your input never leaves your machine.
JSON Formatter & Validator
Format messy JSON, validate syntax and make nested data easier to read.
JSON Diff
Compare two JSON documents structurally and list added, removed and changed values.
JSON to CSV Converter
Flatten nested JSON objects into CSV with configurable delimiters, headers and BOM.
YAML ↔ JSON Converter
Convert configuration between YAML and JSON locally using the js-yaml parser.
Base64 Encoder / Decoder
Convert text to Base64 and decode it back, with input validation and copy buttons.
URL Encoder & Decoder
Percent-encode or decode URL components and complete URIs entirely in your browser.
URL Parser
Split a URL into protocol, host, path, query and fragment, with a decoded query table.
Hash Generator
Compute MD5, SHA-1, SHA-256, SHA-384 and SHA-512 hashes of any text.
JWT Decoder
Decode a JWT header and payload locally in your browser and inspect its claims.
UUID Generator
Generate unique identifiers for test data, development and quick prototyping.
Password Generator
Generate strong random passwords and estimate their resistance to brute-force attacks.
Regex Tester
Test regular expressions with flags, live highlighting and capture group inspection.
Timestamp Converter
Convert between Unix timestamps, ISO 8601 and readable local and UTC dates.
Cron Expression Parser
Explain a five-field cron expression in plain English and preview the next scheduled runs.
Color Converter
Convert colors between HEX, RGB and HSL, with a live picker and preview.
Redirect Generator
Generate nginx or Apache .htaccess redirect rules from a simple old-to-new list.
robots.txt Generator
Build a robots.txt with allow and disallow paths, crawl delay and a sitemap URL.
Security Headers Sanitizer
Check HTTP security headers, find weak values and generate a clean nginx snippet.
Encoding, hashing and tokens
Encode and decode Base64 and URLs, compute MD5 and SHA hashes, inspect JWT claims, and generate UUIDs or strong passwords.
Web configuration utilities
Test regular expressions, convert timestamps and colours, explain cron schedules, and generate redirect or robots.txt rules.
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