FREE • LOCAL • PRIVATE
Code & Data Utilities
Format, convert, validate and explore data without sending your input to a server.
12 Code & Data Tools
JSON Formatter & Validator
Validate, prettify, or minify JSON directly in your browser.
Open tool → FREE • ON-DEVICEYAML ↔ JSON Converter
Convert simple YAML maps and lists to JSON, or JSON to YAML.
Open tool → FREE • ON-DEVICECSV ↔ JSON Converter
Convert CSV tables to JSON objects and JSON objects to CSV.
Open tool → FREE • ON-DEVICEXML Formatter & Validator
Validate XML and serialize it into a clean output.
Open tool → FREE • ON-DEVICEBase64 Encoder & Decoder
Encode Unicode text as Base64 or decode Base64 to UTF-8.
Open tool → FREE • ON-DEVICEURL Encoder & Decoder
Encode URL components or decode percent-encoded text.
Open tool → FREE • ON-DEVICERegex Tester
Try JavaScript regular expressions against test text.
Open tool → FREE • ON-DEVICEUUID Generator
Generate cryptographically random version 4 UUIDs locally.
Open tool → FREE • ON-DEVICEHTML Entity Converter
Encode special HTML characters or decode HTML entities.
Open tool → FREE • ON-DEVICESQL Formatter
Improve SQL statement readability with whitespace formatting.
Open tool → FREE • ON-DEVICEMarkdown Live Preview
Preview basic Markdown formatting safely in your browser.
Open tool → FREE • ON-DEVICEJSON Schema Validator
Check JSON data against supported schema rules.
Open tool →More KOLFAT TOOLS
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