Tool category
Free Online Developer Tools
Developer tools keep common text operations close at hand, with local processing and clear warnings for sensitive inputs.
26 tools in this category
JSON Formatter
Format and beautify JSON online. Paste minified or messy JSON and get clean, 2-space indented output with syntax validation, instant, in-browser, no upload.
Open toolJSON Validator
Validate JSON syntax online with exact error messages. Get line number, column, and a human-readable explanation for every JSON error, processed in your browser.
Open toolJSON Minifier
Minify JSON by removing all whitespace and line breaks. Paste pretty JSON, get compact JSON for APIs, payloads, and config files. Browser-only, free.
Open toolJWT Decoder
Decode and inspect JSON Web Tokens in your browser. See the header, payload, and signature in readable JSON. No server, no logging, completely private.
Open toolBase64 Encode Decode
Encode text to Base64 or decode Base64 to plain text instantly in your browser. Supports standard and URL-safe Base64, Unicode, and binary-safe encoding.
Open toolURL Parser
Parse any URL into its components: protocol, host, port, path, query parameters, and hash fragment, instantly in your browser.
Open toolRegex Tester
Test and debug regular expressions online. Paste your pattern and test string to see all matches highlighted, with capture groups listed and flags explained.
Open toolSQL Formatter
Format and indent SQL queries for readability. Supports SELECT, INSERT, UPDATE, DELETE, JOIN, and subqueries, browser-only, instant formatting.
Open toolUUID Generator
Generate random UUIDs (v4) or time-based UUIDs (v1) in bulk. Copy one or download hundreds as a list, instant, browser-based, no server.
Open toolHash Generator
Generate cryptographic hashes from text in your browser. Supports MD5, SHA-1, SHA-256, and SHA-512. No upload, computed locally using the Web Crypto API.
Open toolDiff Checker
Compare two text blocks side-by-side and see additions, deletions, and unchanged lines highlighted. No upload. Your text stays in the browser.
Open toolYAML Validator
Validate YAML syntax online with precise error messages showing exact line and column. Supports YAML 1.2, anchors, and multi-document streams.
Open toolTOML Formatter
Validate and format TOML files in your browser. Get precise error messages for TOML syntax errors. Browser-only, free.
Open toolMarkdown Table Generator
Build Markdown tables visually. Add rows and columns, edit cells, choose alignment, and copy the pipe table syntax, browser-only, free.
Open toolCron Expression Explainer
Explain any cron expression in plain English. Shows the schedule, next run times, and breaks down each field, browser-based, free.
Open toolcURL Formatter
Format multi-line cURL commands into readable indented syntax. Paste a long cURL command and get a clean, copy-ready version. Browser-only.
Open toolHTTP Header Parser
Parse raw HTTP request or response headers into a structured key-value table. Identifies content type, cache headers, security headers, and more. Browser-only.
Open toolLog Prettifier
Prettify JSON log output from Node.js, Python, or any structured logging framework. Colorised, formatted, and readable, browser-only.
Open toolHTML Entity Encoder Decoder
Encode text to HTML entities or decode HTML entities to plain text. Handles &, <, >, ", and all named and numeric entities.
Open toolURL Encode Decode
URL encode or decode text online. Converts special characters to percent-encoded sequences (%20, %2F, etc.) and back, browser-only, instant.
Open toolJSON to TypeScript
Generate TypeScript interfaces from any JSON object. Paste JSON, get typed TypeScript interfaces with nested types, browser-only, free.
Open toolJSON Path Tester
Test JSONPath expressions against any JSON document. See matching results highlighted in real time, browser-only, no account required.
Open toolPassword Generator
Generate cryptographically strong random passwords in your browser. Set length, character sets, and strength meter. Generated locally. Never transmitted.
Open toolColor Converter
Convert colors between HEX, RGB, HSL, and CSS color names. Enter any color format and see all equivalents instantly. Browser-only, free.
Open toolNumber Base Converter
Convert numbers between decimal, binary, octal, and hexadecimal simultaneously. Type in any base and see all others update live. Browser-only, free.
Open toolUnix Timestamp Converter
Convert Unix timestamps (seconds or milliseconds) to human-readable dates and vice versa. Shows local time, UTC, ISO 8601, and relative time. Browser-only.
Open toolHow this category works
Developer tools include local utilities for JSON, Base64, URLs, headers, hashes, diffs, regex, UUIDs, passwords, color conversion, number bases, Unix timestamps, and more, all processing input client-side.
Related categories
Frequently asked questions
Do developer tools send snippets away from my browser?
Local developer tools process input in the browser unless a page explicitly says otherwise.
Are validators a security guarantee?
No. Validators are helpful checks, but they do not replace a review of your own application or deployment.