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ToolGrid AI

Free Developer Tools

23 free tools

Format JSON, encode Base64 and URLs, generate UUIDs and passwords, convert colors and inspect data formats. They are quick utilities for developers, analysts and students who need a reliable answer without opening an IDE or sharing data with a remote service.

23 matching tools

File Download Time EstimateEstimate transfer time from decimal megabytes and connection megabits per second.Screen Pixel DensityCalculate pixels per inch from screen resolution and diagonal inches.CSV to JSONConvert comma-separated tables with quoted fields to JSON objects.JSON to CSVConvert an array of flat objects to a spreadsheet-safe CSV.HTML Entity EncoderEscape HTML-sensitive characters for literal display in markup.HTML Entity DecoderDecode common named and numeric HTML entities as plain text.JWT Payload DecoderRead a JWT header and payload locally; does not verify its signature.URL ParserInspect a web address, its host, path, query parameters and fragment.UTM Link BuilderBuild campaign links while preserving existing query parameters.Number Base ConverterConvert integers between binary, octal, decimal and hexadecimal.Data Size ConverterConvert decimal KB/MB/GB and binary KiB/MiB/GiB using bytes.JSON to TypeScriptInfer a TypeScript type from a JSON sample, including nested arrays.XML Formatter & ValidatorValidate well-formed XML and indent its elements without fetching resources.Color Contrast CheckerCalculate WCAG contrast for two solid sRGB colors.File SHA-256 ChecksumHash a file locally and optionally compare it with a trusted checksum.Password GeneratorCreate strong random passwords.JSON FormatterFormat, validate and minify JSON.Base64 Encode / DecodeEncode or decode Base64 text.URL Encode / DecodeEncode or decode text for URLs.UUID GeneratorGenerate random v4 UUIDs in bulk.Color ConverterConvert between HEX, RGB and HSL with a picker.Hash GeneratorCreate SHA-1, SHA-256, SHA-384 and SHA-512 hashes.Unix Timestamp ConverterConvert Unix timestamps to dates and back.

Tips for better results

  • Never paste production secrets into any website, even a browser-only one, on a shared computer.
  • Validate JSON before converting it to other formats.
  • Generated passwords are only as safe as where you store them.

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