The developer toolbox that never sees your data
Format JSON, decode JWTs, hash strings, generate UUIDs and passwords, convert Base64, test regex and more — fast, free, and computed entirely in your browser. Nothing you paste is ever uploaded.
Your tools
Favorites and recently used — saved on this device.
Favorites
Recently used
Popular tools
The utilities developers reach for every day.
JSON Formatter
Format, beautify, minify and validate JSON instantly in your browser.
Crypto & SecurityJWT Decoder
Decode and inspect the header and payload of any JWT.
WebRegex Tester
Test regular expressions against text in real time, with live match highlighting.
Crypto & SecurityHash Generator
Generate MD5, SHA-1, SHA-256 and SHA-512 hashes from any text.
WebCron Expression Parser
Translate cron expressions into plain English and build new schedules.
GeneratorsUUID Generator
Generate one or many random version-4 UUIDs instantly.
WebColor Converter
Convert colors between HEX, RGB and HSL, with a live preview.
ConvertersYAML to JSON Converter
Convert YAML to JSON and JSON to YAML instantly.
Browse by category
Everything, organised.
Converters
Transform data between formats.
34 toolsCrypto & Security
Hashes, tokens and secure helpers.
15 toolsWeb
Encoders and web-format helpers.
27 toolsText
Manipulate and inspect text.
50 toolsGenerators
Generate IDs, values and data.
8 toolsReference
Lookups developers reach for daily.
2 toolsFrom the guides
Practical explainers behind the tools.
How to Format and Validate JSON (A Practical Guide)
What JSON formatting really does, the most common errors that break parsers, and how to read a messy payload in seconds.
SecurityWhat Is a JWT and How to Decode One Safely
The three parts of a JSON Web Token, what the claims mean, and why decoding is not the same as verifying.
Web301 vs 302 Redirects: Which to Use and Why It Matters
The SEO and caching differences between permanent and temporary redirects, and how to write the rules for Apache and Nginx.
Portfolio & CV templates
Free, professional website templates — ready to preview and download.
Developer portfolio template
A complete developer portfolio with a project grid, animated skill bars, experience timeline and contact form.
CV & resumeProfessional resume portfolio
A modern CV portfolio with experience, achievements, skills, references and a Download Resume button.
Designer portfolioUI/UX designer portfolio
An elegant designer portfolio with case studies, a design process, tools and a booking section.
Private by design
Every tool runs client-side. Your payloads, tokens and secrets never touch a server, because there is no server-side processing.
Fast & lightweight
No bloated frameworks on tool pages. Server-rendered HTML with focused vanilla JavaScript that loads instantly.
Correct & verifiable
Tool logic is checked against authoritative references and known test vectors, with open-source algorithms credited.
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