Free Developer Tools That Run in Your Browser
JSON, encoding, number conversion, text, colors, hashes and generators. Find the tool for your next task and work directly in your browser.
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Fast. Free. Private. Your data stays in your browser.
Explore by category
Find a place to startJSON Tools
22 toolsInspect API responses, validate syntax, compare documents and convert structured data into formats your workflow needs.
Encoding & Decoding Tools
10 toolsEncode text for transport and inspect Base64, URLs, JWT claims, HTML entities and image data URIs.
Number Converter Tools
21 toolsConvert binary, decimal, hexadecimal and octal values, translate encoded text and work with number lists.
Hash Tools
5 toolsCalculate text digests, compare hash algorithms and generate keyed HMAC values locally.
Text & Web Tools
11 toolsCount words and characters, compare text, test regular expressions, format XML, SQL and HTML, and write Markdown.
Color Tools
3 toolsChoose a color visually, convert HEX, RGB and HSL values, and copy CSS-ready output.
Generators
7 toolsCreate passwords, UUIDs, barcodes, static QR codes, random numbers, cron expressions and placeholder text.
HTTP & Network Tools
6 toolsParse URLs and HTTP headers, inspect status codes and MIME types, and calculate IPv4 subnet information directly in your browser.
Popular tools
13 of 13 tools
JSON Formatter
Format, beautify, validate, minify and pretty print JSON online. Fix common syntax issues, inspect tree view and keep your data private in-browser.
JSON Validator
Validate JSON syntax online and find exact parse errors by line and position. Check JSON, lint common mistakes and keep all data in your browser.
JSON Viewer
View JSON online in a searchable collapsible tree. Explore nested objects and arrays, format raw JSON and inspect large payloads privately in your browser.
JSON to TOON Converter
Convert JSON to TOON for compact LLM prompts. Reduce repeated keys in tabular data, compare token counts and keep conversion entirely in your browser.
Binary Translator
Translate binary code to readable text online and switch to text-to-binary when needed. Decode 8-bit bytes instantly with private browser-side processing.
Random Number Generator
Generate one or many random numbers in any range. Choose unique values, sort results and use quick 1–10 or 1–100 presets instantly online.
Base64 Decode
Decode Base64 to readable text online, including standard and URL-safe strings. Handle Unicode safely and keep encoded data private in your browser.
Case Converter
Convert text between uppercase, lowercase, Title Case, camelCase, PascalCase, snake_case and kebab-case instantly in your browser.
Color Picker & Converter
Pick colors visually and convert between HEX, RGB and HSL online. Adjust sliders, preview colors and copy CSS-ready values instantly.
Password Generator
Generate strong random passwords online with configurable length, numbers, symbols and character sets. Uses browser crypto and never sends passwords away.
QR Code Generator
Create free QR codes from URLs or text online. Customize size, colors and error correction, then download PNG or SVG without uploading your data.
Word & Character Counter
Count words, characters, sentences and reading time instantly. Check character count, keyword density and text length privately in your browser.
Barcode Generator
Generate Code 128, EAN-13, UPC-A, Code 39 and other barcodes online. Customize size and download clean barcode images directly from your browser.
A few useful places to start
Tools that work well togetherJSON Tools
Inspect API responses, validate syntax, compare documents and convert structured data into formats your workflow needs.
Encoding & Decoding Tools
Encode text for transport and inspect Base64, URLs, JWT claims, HTML entities and image data URIs.
Number Converter Tools
Convert binary, decimal, hexadecimal and octal values, translate encoded text and work with number lists.
Work locally, keep control
Tool input is processed in your browser. Paste a sample, inspect the result, then copy or download it when ready. Each tool includes relevant examples, limitations and links to the next step in your workflow.
Read the privacy policyPrivate by designTool input stays in your browser.
Ready to useOpen a tool and get straight to work.
Keep your workflow simpleCopy or download the result when ready.
JSON to TOON, our original converter
Turn repeated JSON records into a compact prompt representation and compare estimated token counts. The dedicated converter keeps its familiar copy, download and reverse-conversion controls.