Secure, offline developer tools that never send your data anywhere.

JSON Editor, OpenAPI Spec Editor, JWT Debugger and UUID Generator — all running entirely in your browser using HTML, CSS and JavaScript.

Open the tools Explore features
No backend No data stored Responsive design No network calls
All processing is happening right here in your browser.

All DevTools, one browser-only workspace.

Each tool is designed to be powerful, focused and 100% client-side.

📄
JSON Editor

A single, spacious editor pane for JSON viewing, editing, formatting and validation.

  • Pretty-print and minify
  • Schema-friendly editing
  • No server calls
Open JSON Editor →
🔧
OpenAPI Spec Editor

Upload your OpenAPI YAML or JSON, edit in place, and download the result.

  • YAML & JSON support
  • In-browser file parsing
  • No data leaves your device
Open OpenAPI Editor →
🔐
JWT Debugger

Decode, inspect, and experiment with JSON Web Tokens safely, locally.

  • Header, payload, signature view
  • Live decoding while you type
  • All logic in JavaScript
Open JWT Debugger →
🔢
UUID Generator

Generate as many UUIDs as you need and copy them with a single click.

  • Multiple UUIDs at once
  • Clipboard-friendly UI
  • Zero backend dependencies
Open UUID Generator →
🔍
Regex Tester

Test and debug regular expressions with real-time highlighting and explanation.

  • Real-time highlighting
  • Cheatsheet included
  • Runs locally
Open Regex Tester →
🤖
LLM Tokenizer

Count tokens and estimate costs for GPT-4, Claude and more.

  • Real-time count
  • Cost estimator
  • Multiple models
Open LLM Tokenizer →
🛡️
IAM Policy Gen

Build visual AWS IAM policies without syntax errors.

  • Visual builder
  • JSON sync
  • Security focused
Open IAM Policy →
☸️
K8s Wizard

Generate valid Kubernetes manifests for Deployments and Services.

  • Visual creation
  • YAML download
  • Multi-resource
Open K8s Wizard →
🕸️
CIDR Visualizer

Plan cloud networks and split subnets interactively.

  • Interactive tree
  • IP range calc
  • VPC planner
Open CIDR Viz →
🔍
JSONPath Tester

Query and extract data from complex JSON documents.

  • Evaluate expressions
  • Filter arrays
  • Debug pipelines
Open JSONPath →
🐳
Docker Compose

Visually design multi-container applications.

  • Visual stack builder
  • Port/Volume mapping
  • YAML generator
Open Docker Compose →
🔄
SQL Converter

Convert SQL tables to Pydantic or TypeScript.

  • SQL to Pydantic
  • SQL to TS
  • Instant conversion
Open SQL Converter →
📈
Prometheus Regex

Test regex for PromQL and Alertmanager routing.

  • RE2 validation
  • Implicit anchoring
  • Match testing
Open Prom Regex →
🔐
Env Encryptor

Securely share .env secrets via one-time links.

  • AES-GCM Encryption
  • Client-side only
  • Zero knowledge
Open Encryptor →
📊
Mermaid Editor

Create diagrams from text with live preview.

  • Flowcharts & Sequence
  • SVG Export
  • Live rendering
Open Mermaid →

How it works

The entire toolbox is implemented with HTML, CSS, and JavaScript. Every operation — parsing JSON, editing OpenAPI specs, decoding JWTs, generating UUIDs — is executed in your browser’s JavaScript runtime.

  1. You open a tool from this page.
  2. The tool runs entirely in your browser tab.
  3. Your content is never sent to any server.

This makes the tools fast, privacy-friendly, and easy to host anywhere as static files.

// Pseudocode
const data = loadFromBrowser();
const result = processLocally(data);
render(result);

// No network requests. No logs. No backend.

Tech stack

The toolbox is intentionally minimal:

  • HTML for structure
  • CSS for layout and responsive design
  • Plain JavaScript for all logic and in-browser processing