59 tools · web + desktop

Developer tools,
local-first.

Your standard output for dev tools — format, convert, encode, generate. 59 tools that run 100% in your browser. No backend, no signup, nothing leaves your machine.

Open the app Star on GitHub
  • 100% client-side
  • No signup
  • Offline-ready
  • MIT licensed
JSON Format / Validate 
{
  "service": "stdout",
  "local": true,
  "tools": 59,
  "sendsData": null,
  "runtime": ["browser", "desktop"]
} 

Built for speed, privacy, and trust

Everything you need for daily dev work — nothing you don't. No dark patterns, no telemetry.

Privacy first

No server, no tracking. Every tool runs in your browser — your data never leaves the machine.

Zero friction

Open and use. No account, no API keys, no install required for the web app.

Works offline

A PWA that keeps working after the first load — on a plane, behind a firewall, anywhere.

Free & open source

MIT licensed. Each tool is isolated and independently extendable. Fork it, ship your own.

Local-first

Your data never leaves your device

Most "online" formatters paste your JWTs, payloads, and secrets straight into someone else's backend. stdout has no backend — processing happens in memory, on your machine.

The invisible tracking risk

How typical browser-based online tools can leak and track sensitive data
  • Third-party analytics (GA, Mixpanel, Hotjar)
  • Browser-fingerprinting scripts
  • CDN compromise & malicious extensions
  • Payloads logged on someone else's server

How stdout works

stdout client-only architecture: tools run in the browser or desktop with no backend
  • Client-only processing — no backend
  • Runs in the browser or as a desktop app
  • No network calls, no payload logging
  • Works offline after first load

59 tools, nine categories

One app for everything that goes to your standard output — organized, searchable (⌘K), tabbed.

Open all tools

Formatters

7
JSON XML HTML SQL CSS JavaScript

Converters

15
JSON ↔ YAML CSV ↔ JSON XML ↔ JSON JSON → Types Timestamp Number Base Color

Encode & Crypto

10
Base64 URL JWT Debugger Hash (MD5/SHA) HMAC QR Code Gzip

Validators

7
Regex Tester JSONPath XPath Schema Diff Payload Compare Cron Builder

Generators

6
UUID Password Random String Mock Data ASCII Art Log

Web Resources

4
Markdown Preview Lorem Ipsum URL Parser MIME Types

String & Utilities

4
Text Diff String Utilities Escaper Text Inspector

Networking & Other

4
cURL Builder HAR Viewer CSV Viewer Math Calculator

Image & Media

2
SVG Viewer Image Resizer

A workspace, not just a page

stdout works like the editor you already live in — keyboard-driven, tabbed, and fast.

  • Multi-tab workspace

    Open several tools at once and switch instantly — open the same tool twice to compare two payloads.

  • JSON tree view

    Collapse, search keys & values, and copy any node's JSONPath or value.

  • Command palette

    ⌘K / Ctrl+K to jump to any of the 59 tools without leaving the keyboard.

  • Themes

    Dark, light, and OLED deep-dark — tuned for long sessions.

The stdout app: tool grid with sidebar navigation and command palette

Use it anywhere

Run it in the browser, or install the native desktop app for offline use.

Web

Recommended

Nothing to install. Works offline after first load.

Open in browser

macOS

Install via Homebrew cask.

brew install --cask cminhho/tap/stdout

Windows · Linux

Download a build from GitHub releases.

Releases

Bring your dev tools home

Format, convert, encode, and generate — locally, privately, for free. No signup required.

Open the app View source