Midtstein Tools

A collection of browser-based developer tools. No install, no signup — just open and use.

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Markdown Preview

Live Markdown preview with Mermaid diagrams, KaTeX math, video/image embeds. Write and preview everything in one place.

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JSON Viewer

Tree view, path copy, search. AI giải thích structure và generate TypeScript interface.

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Prompt Workshop

Test prompt với Claude và GPT. Stream response, compare models side-by-side, save templates.

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Diff Viewer

So sánh text side-by-side hoặc inline. Word-level highlighting, AI tóm tắt thay đổi.

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Code Reviewer

AI-powered code review with severity-tagged issues (Critical, Warning, Info) and one-click refactor suggestions.

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i18n Helper

Compare source and target locale JSON files, detect missing keys, and AI-translate with variable preservation.

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Markdown Editor

Split-pane Markdown editor with live preview, formatting toolbar, and AI rewrite, summarize and translate features.

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Text Transformer

Case transforms, line sorting, find & replace, prefix/suffix and more. AI rewrite, translate and grammar fix.

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Regex Playground

Real-time regex testing with match highlighting, capture groups, common patterns library. AI explains and generates regex from plain English.

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Encoder / Decoder

Base64, JWT decode with expiry badges, URL encode/parse, HTML entities. AI explains JWT claims and security notes.

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Color Toolkit

Color picker, HEX/RGB/HSL/Tailwind converter, WCAG contrast checker, palette generator. AI generates palettes from descriptions.

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SQL Workshop

Format, highlight, and analyze SQL queries. AI generates SQL from natural language and explains queries step by step with performance tips.

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Commit Generator

Generate git commit messages and PR descriptions from diffs. Supports Conventional Commits, Gitmoji, and custom formats with AI streaming.

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CSV ↔ JSON

Convert between CSV and JSON formats. RFC 4180 parser, nested object flattening, sortable table preview. AI describes your dataset.

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Timestamp Tool

Convert Unix timestamps, ISO 8601, RFC 2822 and natural dates. Live clock, timezone converter, date diff calculator.

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cURL Converter

Convert cURL commands to JavaScript, Python, Go, and PHP code — or reverse any fetch/requests call back to cURL. AI generates API calls from plain English.

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HTML Render

Live HTML/CSS/JS editor with instant preview. Sandboxed iframe rendering, built-in console, drag-to-resize panes, and auto-save.

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