ToolDeck

Free OnlineDeveloper Tools

Format JSON, encode Base64, decode JWT, convert YAML, and more — right in your browser.

95 tools · no signup · your data stays on your device

JSON

18
JSON Formatter & BeautifierFormat and beautify JSON with syntax highlightingJSON ValidatorValidate JSON syntax and structureJSON DiffCompare two JSON objects and highlight differencesJSON Pretty PrintPretty print JSON with customizable indentation for readabilityJSON MinifierMinify and compact JSON by removing whitespaceJSON to YAMLConvert JSON to YAML formatJSON to CSVConvert JSON array to CSV formatJSON to TypeScriptGenerate TypeScript interfaces from JSONJSON to C# ClassGenerate C# classes from JSONJSON to Go StructGenerate Go structs from JSONJSON to PythonGenerate Python dataclasses from JSONJSON to JavaGenerate Java POJO classes from JSONJSON to DartGenerate Dart classes from JSON with fromJson and toJsonJSON to XMLConvert JSON to XML formatJSONPath TesterTest JSONPath expressions against JSON data and see matching resultsJSON Schema ValidatorValidate JSON data against a JSON Schema (Draft 7)JSON String EscapeEscape and unescape JSON special characters in stringsJSON to TOMLConvert JSON to TOML format

YAML

2
YAML to JSONConvert YAML to JSON formatYAML to XMLConvert YAML to XML format

Base64

7
Base64 Encode OnlineEncode text or binary data to Base64Base64 Decode OnlineDecode Base64 encoded textBase64 Image DecoderDecode Base64 data URIs back to viewable imagesBase64 Image EncoderEncode images to Base64 data URIs for HTML and CSSBase64 URL-safeEncode and decode URL-safe Base64 (Base64url)Base64 to HexConvert between Base64 and hexadecimalBase64 File EncoderEncode any file to Base64 — PDF, ZIP, images, and more

URL

3
URL Encode OnlineEncode special characters in URLsURL Decode OnlineDecode percent-encoded URLsURL ParserParse a URL into its components — protocol, host, path, query params, hash

JWT

2
JWT EncoderCreate and sign JSON Web Tokens with HS256, HS384, HS512JWT DecoderDecode and inspect JSON Web Tokens

Time

6
Timestamp ConverterConvert Unix timestamps to human-readable dates and backCron Expression ParserParse cron expressions into human-readable descriptions and preview next run timesCron Expression GeneratorGenerate cron expressions visually with a step-by-step builderCron Expression ValidatorValidate cron expressions and see a detailed field-by-field breakdownDate CalculatorCalculate the difference between two dates in years, months, days and moreTimezone ConverterConvert a date and time between timezones worldwide

UUID

10
UUID v4 GeneratorGenerate cryptographically random UUID v4UUID v1 GeneratorGenerate time-based UUID v1 with embedded timestampUUID v7 GeneratorGenerate time-ordered UUID v7 for database primary keysUUID v3 GeneratorGenerate deterministic name-based UUID v3 using MD5UUID v2 GeneratorGenerate DCE Security UUID v2 with local domain and IDULID GeneratorGenerate lexicographically sortable unique IDsNanoID GeneratorGenerate tiny URL-safe unique IDs with customizable alphabetCUID GeneratorGenerate collision-resistant unique IDs (CUID v1)CUID2 GeneratorGenerate secure next-generation CUID2 identifiersUUID DecoderDecode and inspect UUID structure, version, and embedded data

Hash

7
MD5 Hash GeneratorGenerate MD5 hash from any textSHA-1 Hash GeneratorGenerate SHA-1 hash from any textSHA-256 Hash GeneratorGenerate SHA-256 hash from any textSHA-384 Hash GeneratorGenerate SHA-384 hash from any textSHA-512 Hash GeneratorGenerate SHA-512 hash from any textHMAC GeneratorGenerate HMAC signatures with SHA-256, SHA-384, or SHA-512Hash IdentifierIdentify hash type by length and format — MD5, SHA-1, SHA-256, and more

CSV

7
CSV to JSONConvert CSV data to JSON array or object formatCSV to MarkdownConvert CSV to a Markdown tableCSV to HTML TableConvert CSV to an HTML tableCSV FormatterFormat and normalize CSV data with custom delimiter optionsCSV to SQLGenerate SQL INSERT statements from CSV dataCSV to XMLConvert CSV data to XML formatCSV to YAMLConvert CSV data to YAML array of objects

Text

11
Word CounterCount words, characters, sentences, paragraphs and estimate reading timeCase ConverterConvert text between uppercase, lowercase, title case, camelCase, snake_case and moreLorem Ipsum GeneratorGenerate lorem ipsum placeholder text with configurable paragraphs and wordsLine SorterSort lines alphabetically, by length, reverse or randomize line orderDuplicate Line RemoverRemove duplicate lines from text, keeping only unique linesText DiffCompare two texts side by side and highlight line-by-line differencesRegex TesterTest regular expressions against a string and see all matches highlightedMarkdown PreviewPreview Markdown text rendered as HTML in real timePassword GeneratorGenerate strong random passwords with customizable length and character setsSlug GeneratorConvert any text into a clean URL-friendly slugString EscapeEscape and unescape strings for JavaScript, Python, and JSON

Color

6
Color ConverterConvert colors between HEX, RGB, HSL and HSV formats with a visual color pickerColor Contrast CheckerCheck WCAG AA and AAA contrast ratio between foreground and background colorsColor Palette GeneratorGenerate complementary, analogous, triadic and tetradic color palettes from any base colorColor Name FinderFind the closest CSS named color for any HEX or RGB valueCSS Gradient GeneratorBuild linear and radial CSS gradients visually and copy the CSS codeTailwind Color FinderFind the nearest Tailwind CSS color class for any HEX or RGB value

XML

6
XML FormatterFormat and pretty-print XML with syntax highlightingXML MinifierMinify XML by removing whitespace and commentsXML ValidatorValidate XML syntax and check for well-formedness errorsXML to JSONConvert XML to JSON formatXML to YAMLConvert XML to YAML formatXPath TesterTest XPath expressions against XML and see all matching nodes

HTML

5
HTML FormatterFormat and prettify HTML with proper indentationHTML MinifierMinify HTML by removing whitespace and commentsHTML Escape / UnescapeEscape and unescape HTML entities (& < > " etc.)HTML to JSXConvert HTML to JSX for React — class→className, style strings→objectsHTML to MarkdownConvert HTML to Markdown format

CSS

3
CSS FormatterFormat and beautify CSS with proper indentationCSS MinifierMinify CSS by removing whitespace and commentsCSS Unit ConverterConvert CSS units between px, rem, em, vw, vh and %

TOML

2
TOML to JSONConvert TOML to JSON formatTOML FormatterFormat and validate TOML configuration files

Developer tools that just work

ToolDeck is a free collection of online utilities built for developers who need fast, reliable tools without friction. Format and validate JSON, encode or decode Base64, inspect JWT tokens, convert between JSON and YAML, encode URLs, and convert Unix timestamps — all without signing up, installing anything, or leaving your browser. Every tool runs entirely client-side, so your data stays on your device.