20 local browser tools
All Free Online Developer Tools
Find private browser-based tools for JSON, encoding, generators and date conversion.
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Try searching for JSON, CSV, JWT, Base64, URL, timestamp or hash.
3 tools
JSON Tools
Format, validate and minify JSON in your browser with clear errors and private local processing.
JSON Formatter
Beautify JSON and validate syntax with readable indentation and precise parse errors.
JSON Tools · JSON text → Formatted JSON ✓JSON Validator
Check whether JSON is valid and see clear syntax errors before using it in code.
JSON Tools · JSON text → Validation result ⇥JSON Minifier
Remove whitespace from valid JSON to create compact payloads and fixtures.
JSON Tools · JSON text → Minified JSON7 tools
Encoding Tools
Encode and decode Base64, URLs and other transport-safe formats without sending values to a server.
Base64 Encoder
Encode Unicode text as Base64 for transport in configuration, headers and scripts.
Encoding Tools · Plain text → Base64 text AaBase64 Decoder
Decode Base64 text back to UTF-8 so encoded payloads are easy to inspect.
Encoding Tools · Base64 text → Decoded text %URL Encoder
Percent-encode text for safe use in URLs, query strings and redirect parameters.
Encoding Tools · Text → URL-encoded text /URL Decoder
Decode percent-encoded URL text into readable characters.
Encoding Tools · URL-encoded text → Decoded text &;HTML Entity Encoder
Encode reserved HTML characters so text can appear safely inside markup examples.
Encoding Tools · Text → HTML-encoded text <>HTML Entity Decoder
Decode HTML entities back into readable text for debugging copied markup.
Encoding Tools · HTML-encoded text → Decoded text \uUnicode Escape and Unescape
Convert text to JavaScript-style Unicode escapes or decode Unicode escape sequences.
Encoding Tools · Text or Unicode escapes → Converted text2 tools
Generator Tools
Generate UUIDs, secure passwords and other developer-ready values locally in your browser.
1 tools
Date and Time Tools
Convert Unix timestamps and inspect date values across UTC and local time for debugging and logs.
1 tools
Text Tools
Clean, compare and transform plain text.
4 tools
Converter Tools
Convert data between common developer formats.
JSON to YAML Converter
Convert valid JSON into readable YAML for configuration files and documentation.
Converter Tools · JSON text → YAML text JYAML to JSON Converter
Convert YAML documents into formatted JSON with clear parse errors.
Converter Tools · YAML text → Formatted JSON CSVJSON to CSV Converter
Convert arrays of JSON objects into CSV for spreadsheets, QA checks and exports.
Converter Tools · JSON array → CSV text []CSV to JSON Converter
Convert CSV text with headers into formatted JSON arrays.
Converter Tools · CSV text → Formatted JSON array2 tools
Security Tools
Security-oriented helpers that keep sensitive input local.
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