Useful for
- Inspecting API payloads quickly.
- Cleaning a CSV before import.
- Checking a regex against awkward samples.
Format, validate, compare and convert JSON, XML, CSV, HTML, CSS, JavaScript and encoded data in the browser.
Developer Tools
A pretty result isn't automatically a correct one. Use these utilities to inspect structure and syntax, then validate against the schema or application that will actually consume the output.
Browse developer tools
JSON Formatter
Pretty-print JSON with readable indentation.
JSON Validator
Validate JSON syntax and report parsing errors.
JSON Minifier
Remove unnecessary whitespace from valid JSON.
JSON to CSV
Convert an array of JSON objects into CSV locally.
CSV Cleaner
Trim cells, remove blank rows and normalise CSV data.
CSV Duplicate Remover
Remove duplicate CSV rows based on all columns or one column.
XML Formatter
Format XML with readable indentation.
XML Minifier
Remove unnecessary whitespace between XML tags.
XML to JSON
Convert XML elements and attributes into JSON.
HTML Formatter
Pretty-print HTML markup with readable indentation.
HTML Minifier
Remove comments and unnecessary whitespace from HTML.
CSS Minifier
Compress CSS by removing comments and extra whitespace.
JavaScript Minifier
Conservatively reduce JavaScript whitespace and comments.
Base64 Encoder
Encode UTF-8 text into Base64.
Base64 Decoder
Decode Base64 text back into UTF-8.
URL Encoder
Percent-encode text for use in URL components.
URL Decoder
Decode percent-encoded URL text.
HTML Entity Encoder
Escape text for safe display as HTML text.
HTML Entity Decoder
Convert HTML entities back into normal text.
Regex Tester
Test JavaScript regular expressions against sample text.
JWT Decoder
Decode JWT header and payload sections without verifying the signature.
SQL Formatter
Format common SQL statements with line breaks and indentation for easier reading.
HEX RGB HSL Color Converter
Convert colours between HEX, RGB and HSL formats.
Cron Expression Helper
Build common five-field cron expressions from simple scheduling options.
JSON Diff
Compare two JSON values and list changed paths.
CSV Sorter
Sort CSV rows by a selected column while keeping the header row.
CSV Filter
Filter CSV rows that contain a value in a selected column.
JSON Path Finder
Search JSON keys and values and return matching dot-style property paths.
Small developer jobs still need exact rules
A formatter should not quietly change data. A decoder should not pretend it verified a signature. A minifier should make code smaller without changing what the code does. Those boundaries sound obvious—until a quick utility crosses one.
The developer collection keeps those jobs separate: JSON and XML formatting, CSV cleaning, Base64 and URL encoding, regex tests, hashes, minifiers and conversion helpers. Use them as inspection tools, then run the output in the environment that will actually consume it.
Production data has edge cases. Duplicate CSV headers, Unicode, malformed quoting, JavaScript regular-expression literals and encoded URLs all deserve more care than a happy-path demo.
Don’t confuse
- JWT decoding with signature verification.
- JSON syntax validation with schema validation.
Want the deeper reasoning? Read the practical guide for this category.