Solve technical challenges instantly with articles and tools
A technical resource site that fulfills developers' "want to know" and "want to try" needs in the shortest possible time. Deepen your knowledge with practical technical articles and support implementation with browser-based tools that require no registration. We provide a consolidated resource to accelerate daily development work, from front-end to back-end.
Purpose of this site
To answer the "How do I implement this?" or "I just want to check something" moments developers face, we've gathered technical knowledge and handy tools in one place. We provide an environment where you can shorten research time and focus on essential development work.
Who is it for?
For engineers who value efficiency in daily tasks, developers wanting to catch up on technology, and tech leads who want to perform quick verifications. Useful for everyone from beginners to veterans as an aid for technical decision-making and implementation.
Why is it useful?
Because reliable technical articles and instantly usable verification tools are paired, the transition from leaning to practice is smooth. All tools run locally, so you can verify with business data without worrying about security.
Difference from other sites
It's not just a collection of tools, nor just a blog media. It's a comprehensive platform for engineers that emphasizes the experience of "understanding with articles and trying with tools," pursuing professional-level quality and usability.
Recent Articles
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Make Markdown Table Creation Dramatically Easier! Visual Editor Tips
Creating tables in Markdown manually is a pain we've all felt. Learn how to drastically improve your documentation efficiency by using a tool that allows you to create and edit tables with intuitive visual operations.
Understanding Base64 Encoding: How It Works and When to Use It
A deep dive into Base64, Base58, and Base32 encoding mechanisms. Learn about data overhead, binary data handling, and common use cases for developers.
Mastering Cron Syntax: From Basic Concepts to Advanced Scheduling
A comprehensive guide to Cron syntax for developers. Learn the meaning of the 5 fields, how to use special characters (* , / ? L W #), and common scheduling examples.
Visualizing GitHub Actions Workflows: Understanding Complex Pipelines
Learn how to visualize YAML files spanning hundreds of lines using Mermaid.js. Map out job dependencies (needs) graphically to maximize debugging efficiency.
Hashing and HMAC: Essential Security Concepts for Developers
Learn about hash functions like SHA-256, the importance of Salting, and how HMAC works to ensure data integrity and authenticity in your applications.
The Basics of Text Differentiation (Diff): Improving Review and Version Control
Learn how Diff tools instantly highlight 'what changed.' Understand line-by-line and character-level comparisons, merging, and how to stay productive.
UUID (Universally Unique Identifier) Fundamentals: Types and Best Practices
Understand what UUIDs are, the differences between v1, v4, and v7, how to use them as database primary keys, and why randomness matters for developers.
Introduction to Regular Expressions for Engineers: Useful Patterns and Basics
A beginner-friendly guide covering basic metacharacters, practical patterns like Email/URL validation, and performance considerations.
Tools
Time & date
Time Zone Converter
Swap between any two time zones instantly (default UTC and JST) to sanity-check launch, meeting, or deploy times.
Time Units
Convert milliseconds through weeks at once and compare results for TTLs, delays, and retry windows.
UNIX Timestamp Converter
Convert UNIX timestamps (seconds or milliseconds) to UTC and local time instantly to validate logs and alerts.
Cron Editor & Parser
Parse Cron expressions into human-readable format and calculate next execution times for schedule verification.
URLs & text
URL Encode / Decode
Encode or decode URLs without leaving your browser to catch slug issues or encoding gaps.
URL Params → JSON
Turn query strings into JSON objects for quick inspection when debugging APIs or webhooks.
Regex Tester
Validate patterns, flags, and captured groups in one view to mirror production-like tests.
Text & Code Suite
Count text, escape HTML/XML, minify CSS/JS, and generate passwords for quick publishing checks.
Markdown Table Generator
Create and edit Markdown tables visually with CSV import/export and column alignment controls.
JSON & schemas
JSON Formatter
Pretty-print or minify JSON for quick validation of payloads and logs.
JSON → TypeScript
Generate TypeScript interfaces from JSON instantly for API responses and configs, including optional/null hints.
JSON → Zod
Infer Zod schemas from sample JSON for parsing or runtime validation and share contracts quickly.
JSON → OpenAPI
Generate OpenAPI component schemas from example JSON in the browser to prep review-ready drafts.
JSON ⇔ YAML
Paste JSON or YAML and convert both ways with copy helpers for config or docs handoffs.
GitHub Actions Visualizer
Visualize and build GitHub Actions workflow YAML with interactive diagrams in the browser.
Security & IDs
Base64 / 58 / 32
Switch tabs to encode or decode with any base in one place while comparing lengths and URL safety.
JWT Tool
Create and decode HS256-signed tokens in the browser without sending keys out of your session.
Hash & HMAC Generator
Generate SHA-1, SHA-256, SHA-512 hashes and HMAC signatures instantly in the browser for secure data verification.
JWKS Generator
Build RSA key pairs, publish public JWKS, and sign RS256 JWTs locally to rehearse key rotation.
UUID Generator
Generate UUIDv4 identifiers and copy instantly for tests or collision checks.
Compare & share
Diff Viewer
Visualize text changes with inline highlighting to confirm edits before commits or reviews.
Color Utility
Convert between HEX, RGB, and HSL colors and check WCAG contrast ratios in real-time for accessible design.
QR Generator
Turn any text or URL into a QR code and save as PNG for sharing Wi‑Fi setups or quick links.
QR Reader
Scan codes with the browser camera and decode locally without sending images to a server.