HubApril 2026·19 tools
19 Free Developer Tools Online
A toolkit for the daily tasks developers face outside of their IDE: formatting data, testing patterns, comparing files, encoding strings, and generating identifiers. These browser-based tools are faster than installing CLI utilities and available from any device.
📋
JSON Formatter
Format, validate, and minify JSON with syntax highlighting and error detection.
✨
Code Beautifier
Format HTML, CSS, JavaScript, and JSON with consistent indentation and style.
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Code Minifier
Minify HTML, CSS, and JavaScript by removing whitespace, comments, and shortening variables.
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Diff Checker
Compare two texts side-by-side with highlighted additions, deletions, and changes.
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Regex Tester
Write, test, and debug regular expressions with real-time match highlighting.
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SQL Formatter
Format SQL queries with proper indentation, keyword casing, and clause separation.
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XML Formatter
Prettify and validate XML documents with proper indentation and syntax checking.
📝
YAML Formatter
Format YAML documents with consistent indentation and validate syntax.
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Hash Generator
Generate MD5, SHA-1, SHA-256, and SHA-512 hashes from any text input.
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Password Generator
Create cryptographically secure passwords with customizable length and character rules.
🆔
UUID Generator
Generate v4 UUIDs for database keys, session tokens, and distributed system identifiers.
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Base64 Encoder/Decoder
Encode and decode Base64 strings for data URIs, API payloads, and file embedding.
🎫
JWT Decoder
Decode JSON Web Tokens to inspect header, payload, and claims.
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HTML Entity Encoder
Encode and decode HTML entities for special characters and symbols.
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Number Base Converter
Convert between binary, octal, decimal, and hexadecimal number systems.
⏰
Cron Builder
Build cron expressions visually with plain-English descriptions of the schedule.
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Chmod Calculator
Convert between numeric and symbolic Unix file permission formats.
📡
HTTP Status Codes
Browse all HTTP status codes with descriptions, use cases, and examples.
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Timestamp Converter
Convert between Unix timestamps, ISO 8601, and human-readable date formats.
📚 References & Further Reading