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開発者ツール
100以上の開発者向けツール。登録不要、制限なし。すべてブラウザ内で処理 — データはデバイスから送信されません。
JSONフォーマッター
JSONをフォーマット、検証、整形。構文ハイライト対応
Base64エンコーダー/デコーダー
テキストをBase64にエンコード、Base64をデコード
URLエンコーダー/デコーダー
URLコンポーネントとクエリパラメータのエンコード/デコード
ハッシュジェネレーター
テキストからMD5、SHA-1、SHA-256、SHA-512ハッシュを生成
マルチハッシュジェネレーター
テキストやファイルからMD5、SHA-1、SHA-256、SHA-384、SHA-512ハッシュを同時生成
UUIDジェネレーター
ランダムUUID (v4) を一括生成
Unixタイムスタンプ変換
Unixタイムスタンプと日付を相互変換
色変換
HEX、RGB、HSL形式間で色を変換、プレビュー付き
正規表現テスター
正規表現をリアルタイムでマッチ＆ハイライト
Markdownプレビュー
Markdownを記述してレンダリングプレビューを表示
JWTデコーダー
JSON Web Tokenをデコードしてヘッダー、ペイロード、署名を確認
QRコード生成
テキスト、URL、任意のデータからQRコードを生成
Lorem Ipsum生成
段落、文、単語のプレースホルダーテキストを生成
HTMLエンティティエンコーダー
HTMLエンティティと特殊文字のエンコード/デコード
CSS圧縮 / 整形
CSSを圧縮または整形
進数変換
2進、8進、10進、16進数を相互変換
Text Converter
Convert text between different cases and formats - lowercase, uppercase, title case, sentence case, alternating case, and inverse case
テキスト差分
2つのテキストを比較して差分をハイライト
文字カウンター
単語、文字、文、段落をカウント
パスワード生成
カスタマイズ可能な安全なランダムパスワードを生成
SQLフォーマッター
SQLクエリをフォーマットして可読性を向上
Cron式パーサー
Cron式を解析し次回実行時刻を表示
JSON ↔ YAML変換
JSONとYAML形式を即座に変換
命名形式変換
camelCase、snake_case、kebab-case等で変換
URLスラッグ生成
テキストをSEOフレンドリーなURLスラッグに変換
行ソート＆重複削除
行をソート、重複削除、反転、シャッフル等
JS/HTMLフォーマッター
JavaScriptとHTMLを圧縮または整形
画像Base64変換
画像をBase64文字列とdata URIに変換。ドラッグ＆ドロップ対応
Git Command Generator
Searchable Git cheat sheet with 90+ commands
XMLフォーマッター
XMLをフォーマット、圧縮、検証
CSV ↔ JSON変換
CSVとJSON形式を即座に変換
HTTPステータスコード参照
HTTPステータスコードの意味を検索
MIMEタイプ検索
ファイル拡張子でMIMEタイプを検索
Escape / Unescape
HTML、JavaScript、JSONのエスケープ/アンエスケープ
IPサブネット計算
サブネットマスク、ネットワーク、ブロードキャストを計算
ダミーデータ生成
テスト用のダミー名、メール、住所を生成
HMACジェネレーター
メッセージとシークレットからHMAC-SHA256、HMAC-SHA1を生成
URLパーサー
URLをコンポーネントに解析
テキスト ↔ バイナリ変換
テキストをバイナリに、バイナリをテキストに変換
PEM / 証明書デコーダー
PEM証明書をデコード
HTMLテーブル生成
CSVまたはJSONをHTMLテーブルに変換
Bcrypt Hash生成
コスト可変のbcryptハッシュを生成
JSON → TypeScript
JSONデータをTypeScriptインターフェースと型に変換
HTML → JSX
HTMLマークアップをReact JSXコンポーネントに変換
JSON から Go へ
JSONをGo構造定義にオンラインで変換
JSON to Go Struct コンバーター
カスタマイズ可能なオプション付きで JSON から Go Struct 定義を生成します
SVG → JSX/React
SVGマークアップをJSX Reactコンポーネントに変換
CSS → Tailwind
CSSスタイルをTailwind CSSユーティリティクラスに変換
TypeScript → JavaScript
TypeScriptコードをプレーンJavaScriptにコンパイル
JSON to GraphQL
Convert JSON data to GraphQL schema definitions
JSON to Java Class
Convert JSON data to Java class definitions
JSON to Kotlin
Convert JSON data to Kotlin data classes
JSON to Python
Convert JSON to Python dataclass, TypedDict, or Pydantic model
JSON to C#
Convert JSON data to C# class definitions
Markdown to HTML
Convert Markdown text to HTML markup
HTML to Markdown
Convert HTML markup to Markdown text
TOML to YAML / YAML to TOML
Convert between TOML and YAML configuration formats
JSON to Zod Schema
Convert JSON data to Zod validation schemas
JSON to JSON Schema
Generate JSON Schema from JSON data
CSS to JS Object
Convert CSS styles to JavaScript style objects
GraphQL to TypeScript
Convert GraphQL schema to TypeScript types
JSON to Rust Struct
Convert JSON data to Rust struct definitions with serde
XML to JSON
Convert XML markup to JSON format
CSSグラデーション生成
ビジュアルエディタでCSSグラデーションを作成
Box Shadow生成
CSSボックスシャドウをビジュアルでデザイン
Metaタグ生成
HTMLメタタグ、OG、Twitterカードを生成
Schema Markup生成
JSON-LD構造化データを生成
Robots.txt生成
robots.txtファイルを生成
JSONビューア / ツリー
JSONデータをインタラクティブなツリーで表示
JSONパスファインダー
JSONを貼り付け、ノードをクリックしてJSONPathを取得
Favicon生成
テキストや絵文字からFaviconを作成
ASCIIアート生成
テキストをASCIIアートに変換
SVG最適化
SVGファイルを最適化・圧縮
プレースホルダー画像生成
カスタムサイズのプレースホルダー画像を生成
カラーパレットジェネレーター
調和のとれたカラーパレットを生成
Flexboxジェネレーター
ビジュアルFlexboxレイアウトビルダー
絵文字ピッカー
絵文字を検索してUnicodeをコピー
ボーダー角丸ジェネレーター
CSS角丸を個別に制御
CSS Unit Converter
Convert between CSS units like px, rem, em, vw, vh
OG画像プレビュー
SNSでの共有表示をプレビュー
Tailwind CSSカラー
Tailwind CSS全カラーパレット
YAMLバリデーター
YAML構文を検証しフォーマット
.gitignoreジェネレーター
あらゆる言語用の.gitignoreを生成
JSON to Dart
Convert JSON to Dart/Flutter classes
Nginx設定ジェネレーター
Nginx設定ファイルを生成
.htaccess Generator
Generate Apache .htaccess rules
Docker Compose Generator
Visual docker-compose.yml builder
JSON to Protobuf
Convert JSON to protobuf
CSPヘッダー生成
コンテンツセキュリティポリシーを構築
SQL→Prisma変換
SQLをPrismaスキーマに変換
Cron式ジェネレーター
ビジュアルエディタでCron式を作成、検証、理解します
テキストからPDF変換
プレーンテキストをカスタム書式オプション付きでPDFドキュメントに変換
Chmod計算
チェックボックスでLinuxファイル権限を計算
16進数→ 10進数変換
16進数、10進数、2進数の数値システム間で変換
YAML ↔ JSON コンバーター
YAMLとJSON形式間をリアルタイムプレビュー付きで変換
Hex→RGB変換ツール
HexカラーコードとRGB値をカラープレビュー付きで変換
8進数10進数変換ツール
8進数と10進数の相互変換（2進数・16進数出力付き）
ローマ数字変換ツール
数字とローマ数字の相互変換（日付変換機能付き）
Byte Converter
Convert between bytes, KB, MB, GB, TB and other file size units
ASCII Text Converter
Convert between ASCII codes and text characters with reference table
Hex to Binary Converter
Convert between hexadecimal and binary number systems
Fraction Decimal Converter
Convert between fractions and decimal numbers with simplification
Scientific Notation Converter
Convert between scientific notation and standard numbers
Color Name to Hex Converter
Convert CSS color names to hex codes, RGB and HSL values
Text Repeater
Repeat text or characters multiple times with separator options
Em/Px Converter
Convert between em, rem, px and other CSS units
IP to Binary Converter
Convert IP addresses to binary and binary to IP format
Unix Timestamp Converter
Convert between Unix timestamps and human-readable dates
MD5 Hash Generator
Generate MD5 hashes from text or files instantly. Free online MD5 checksum calculator
SHA-256 Hash Generator
Generate SHA-256 hashes from text instantly. Free online SHA256 hash calculator
SHA-1 Hash Generator
Generate SHA-1 hashes from text instantly. Free online SHA1 hash calculator
SHA-512 Hash Generator
Generate SHA-512 hashes from text instantly. Free online SHA512 hash calculator
Base64 Encoder
Encode text and strings to Base64 format instantly. Free online Base64 encoding tool
Base64 Decoder
Decode Base64 strings back to plain text instantly. Free online Base64 decoding tool
Base64 to Hex Converter
Convert between Base64 and hexadecimal formats. Free online Base64-Hex converter
String to Base64 Converter
Convert strings to Base64 encoding with UTF-8 support. Free online string encoder
JSON Beautifier
Beautify and pretty-print JSON data with customizable indentation. Free online JSON beautifier
JSON Validator
Validate JSON syntax and find errors with detailed error messages. Free online JSON checker
JSON Minifier
Minify and compress JSON data by removing whitespace. Free online JSON minification tool
JWT Token Decoder
Decode and inspect JWT tokens online. View header, payload, and signature instantly
JWT Parser
Parse JWT tokens and extract claims, expiration, issuer, and audience fields
JWT Validator
Validate JWT token structure, expiration time, and claims. Check if JWT is expired
Regex Checker
Check and test regular expressions against text with match highlighting. Free online regex checker
Regex Matcher
Find all regex matches in text with capture groups and match positions. Free online regex matcher
Regex Generator
Generate regular expressions from common patterns. Email, URL, phone, date regex patterns
Crontab Generator
Generate crontab expressions with visual schedule builder. Free online crontab maker
Cron Job Scheduler
Schedule cron jobs with an interactive visual editor. Preview next run times
Cron Expression Parser
Parse and explain cron expressions in plain English. Understand any cron schedule
URL Decoder
Decode URL-encoded strings back to readable text. Free online URL decoding tool
URL Encode Online
Encode text for safe use in URLs. Free online URL encoding tool with encodeURIComponent
Percent Encoding Tool
Convert characters to percent-encoded format for URLs. Complete percent encoding reference
MD5 vs SHA-256
Compare MD5 and SHA-256 hash algorithms: speed, security, output length, and when to use each
Base64 vs URL Encoding
Compare Base64 and URL encoding: purpose, character sets, size overhead, and when to use each
JSON vs YAML
Compare JSON and YAML data formats: syntax, readability, comments, use cases, and which to choose
JWT vs Session
Compare JWT tokens and session-based authentication: scalability, security, storage, and best practices
REST vs GraphQL
Compare REST APIs and GraphQL: architecture, data fetching, performance, and when to use each
JSON vs XML
Compare JSON and XML data formats: syntax, size, parsing speed, schema support, and use cases
MySQL vs PostgreSQL
Compare MySQL and PostgreSQL databases: performance, features, JSON support, and when to use each
npm vs Yarn vs pnpm
Compare npm, Yarn, and pnpm package managers: speed, disk usage, features, and which to choose
Docker vs Kubernetes
Compare Docker and Kubernetes: containerization vs orchestration, complexity, scaling, and use cases
TypeScript vs JavaScript
Compare TypeScript and JavaScript: type safety, tooling, performance, and when to use each
JSON to Table
Convert JSON data to an interactive, sortable HTML table with search, filter, and CSV export
Base64 画像変換ツール
画像を Base64 文字列に変換、または Base64 を画像に変換
JWT デコーダーオンライン
JWTトークンを無料でオンラインデコード
JavaScript 圧縮ツール
コメント、空白、改行を削除してJavaScriptコードを圧縮
正規表現テスター オンライン
リアルタイムマッチングで正規表現をオンラインテスト
UUID v4 Generator
Generate random UUID v4 identifiers in bulk with uppercase and no-dash format options
HEX Color Picker & Converter
Pick any color visually and get HEX, RGB, HSL, and CMYK values with live preview
Cron Expression Generator
Build, validate, and understand cron expressions with a visual editor
文字列ケースコンバーター
14種類の命名形式間でテキストを変換：camelCase、snake_case、kebab-case、PascalCase など
HTMLエンティティ エンコーダー/デコーダー
名前付きおよび数値エンティティのサポートでHTMLエンティティをエンコード/デコード
JSON→CSV変換ツール
JSON配列をCSV形式に変換。ネストされたオブジェクトの展開とCSVダウンロードに対応
テキストカウンターと統計
単語数、文字数、文数、段落数、行数、バイト数、読み取り時間、話す時間をカウント
画像からBase64エンコーダー
画像をBase64文字列とData URIに変換、ドラッグ&ドロップ対応
テキストケースコンバーター
camelCase、snake_case、kebab-case、PascalCase、UPPERCASE、lowercase、Title Case、dot.caseなどの形式間でテキストを変換
画像圧縮ツール
調整可能な品質で画像を無料でオンライン圧縮。JPEG、PNG、WebP出力対応
Online JSON Editor
Edit JSON data with a tree view editor or raw text editor. Format, validate, and manipulate JSON online
Password Strength Checker
Test your password security with real-time strength scoring, crack time estimation, and detailed analysis
HTML Beautifier & Formatter
Format, beautify, and clean up messy HTML code with customizable indentation options
YAML to JSON Converter
Convert YAML to JSON online. Paste YAML configuration and get clean formatted JSON output instantly
RGB to HEX Converter
Convert RGB color values to hexadecimal color codes with interactive sliders and live color preview
Online Hash Generator
Generate MD5, SHA-1, SHA-256, SHA-384, SHA-512 hashes online. Free hash calculator with multiple algorithms.
JSON Beautifier Online
Beautify and pretty-print JSON data online. Free JSON formatter with validation, sorting, and minification.
CSS Flexbox Generator
Visual CSS Flexbox playground and code generator. Set flex properties interactively and get ready-to-use CSS code.
SVG to PNG 変換
SVGファイルをカスタムサイズと背景のPNG画像に変換
Password Generator Online
Generate strong, secure random passwords online with customizable length, characters, and bulk generation.
YAML Validator Online
Validate YAML syntax online with detailed error messages and line numbers.
IP Address Lookup
Look up IP address geolocation, ISP, and network information. Auto-detects your current IP.
Markdownテーブルジェネレーター
Create and format Markdown tables visually
Base64 Decoder Online
Decode Base64 strings, files, and images online for free. Fast, secure client-side Base64 decoding with image preview
JSON to YAML Converter
Convert JSON to YAML online with real-time live preview. Free, fast, and secure conversion tool for developers
HTML to Markdown Converter
Convert HTML to clean Markdown syntax online. Supports headings, links, images, lists, tables, code blocks
CSS Grid Generator
Visual CSS Grid layout builder. Create grid layouts interactively and get ready-to-use CSS and HTML code
Base64 to Image Converter
Decode Base64 strings to images online. Paste a Base64-encoded image and instantly preview and download it.
CSV to JSON Converter
Convert CSV data to JSON format online. Supports headers, custom delimiters, and nested objects.
JSON Minify Online
Minify and compress JSON data online. Remove whitespace and formatting for smaller file sizes.
JSON to XML Converter
Convert JSON to XML format online. Handles nested objects, arrays, and attributes.
Text to Binary Converter
Convert text to binary and binary to text online. Supports ASCII, UTF-8, and custom encoding formats.
Color Picker Online
Pick colors from a palette, convert between HEX, RGB, HSL, and CMYK formats with a visual color picker.
Lorem Ipsum Generator
Generate placeholder text in paragraphs, sentences, or words. Customize length and format for your designs.
UUID Generator Online
Generate UUIDs (v1, v4, v7) online instantly. Copy bulk UUIDs with one click for your applications.
Base64 Encode Online
Encode text to Base64 format online. Supports UTF-8, ASCII, and binary data encoding with instant results.
cURL to JavaScript Converter
Convert cURL commands to JavaScript fetch or axios code. Supports headers, POST data, authentication, and more.
JavaScript to TypeScript Converter
Convert JavaScript code to TypeScript with type annotations. Add interfaces, type guards, and strict typing.
JSON Schema Generator
Create JSON Schema from JSON online. Free tool to generate JSON Schema with types, required fields, and validation rules.
JSON to CSV Converter Online
Convert JSON arrays and objects to CSV format online. Handles nested data, custom delimiters, and header extraction.
JSON to Zod Schema Converter
Convert JSON data to Zod validation schemas for TypeScript. Generate type-safe runtime validators automatically.
TypeScript to JavaScript Converter Online
Convert TypeScript code to clean JavaScript online. Remove types, interfaces, enums, and generics automatically.
HTML Minifier Online
Minify HTML code online. Remove comments, collapse whitespace, remove empty attributes, and optimize HTML for production.
URL Encoder & Parser Tool
Encode, decode, and parse URLs online. Supports encodeURI, encodeURIComponent, URL parsing, and query parameter extraction.
CSS Gradient Generator
Create beautiful CSS gradients with a visual editor. Linear, radial, and conic gradients with live preview and code output.
JSON Diff Tool
Compare two JSON objects side by side. Highlight differences, additions, and deletions with a visual diff viewer.
Base64 Image Decoder
Decode Base64 strings to images or encode images to Base64 format. Preview decoded images instantly in the browser.
JSON to XML Converter
Convert JSON to XML
Markdown Editor Online
Write and preview Markdown in real-time with syntax highlighting. Export to HTML with a full-featured online editor.
Regex Builder
Build and test regular expressions visually with real-time matching, group highlighting, and common pattern library.
CSS Box Model Visualizer
Interactive CSS box model visualizer showing margin, border, padding, and content areas with editable values.
JavaScript Event Loop Visualizer
Visualize the JavaScript event loop with call stack, task queue, microtask queue, and Web APIs step by step.
HTTP Header Analyzer
Parse and analyze HTTP response headers. Understand each header purpose, detect security issues, and get recommendations.
ASCII Art Generator
Convert text to ASCII art with multiple font styles including Banner, Block, Shadow, Small, and Standard.
DNS Lookup Tool
Perform DNS lookups showing A, AAAA, CNAME, MX, NS, TXT, and SOA records using Google DNS-over-HTTPS.
Color Palette Generator
Generate beautiful color palettes with harmony rules, export to CSS, Tailwind, and design tools.
Crontab Guru
Understand and build cron expressions with human-readable explanations and next execution times.
CSS Animation Generator
Create CSS animations and keyframes visually with live preview, timing functions, and code export.
JSON Path Tester
Test and evaluate JSONPath expressions against JSON data with real-time results and syntax highlighting.
YAML to JSON Converter
Convert YAML to JSON and JSON to YAML online with syntax validation and formatting options.
SQL Formatter Online
Format and beautify SQL queries online with syntax highlighting, indentation options, and support for multiple SQL dialects.
JWT Debugger
Decode and inspect JWT tokens. View header, payload, signature, and expiration status.
XML to JSON Converter
Convert XML data to JSON format online. Fast, free, and easy to use XML to JSON converter.
String Hash Generator
Generate MD5, SHA-1, SHA-256, and SHA-512 hashes from any text string using Web Crypto API.
CSS Specificity Calculator
Calculate CSS selector specificity scores online. Understand which styles take priority with this visual specificity calculator.
Open Graph Preview
Preview and debug Open Graph meta tags. See how your links appear on Facebook, Twitter, LinkedIn, and other social platforms.
SVG to CSS Converter
Convert SVG images to CSS background images using data URIs. Optimize SVGs for CSS usage with encoding and minification.
Responsive Breakpoint Tester
Test responsive breakpoints visually. Preview how your site looks on mobile, tablet, and desktop screens.
JWT Generator
Generate JWT tokens
DNS Record Checker
Check DNS records for any domain. Look up A, AAAA, CNAME, MX, TXT, NS, SOA, and SRV records.
CORS Tester
Test CORS headers for any URL. Check Access-Control-Allow-Origin, methods, headers, and credentials support.
HTTP Request Builder
Build and preview HTTP requests. Construct GET, POST, PUT, DELETE requests with headers and body.
JSON to YAML Converter
Convert JSON to YAML online. Free JSON to YAML converter with proper indentation and formatting.
YAML to JSON Online
Convert YAML to JSON online. Free YAML to JSON converter with validation and pretty printing.
Base64 Decode
Decode Base64 strings online. Free Base64 decoder that converts Base64 back to text instantly.
HEX to RGBA Converter
Convert HEX color to RGBA with alpha transparency support. Free online HEX to RGBA color converter.
CSS Animation Playground
Build CSS animations visually. Create keyframe animations with live preview and code generation.
Docker Run to Compose
Convert docker run commands to docker-compose.yml format. Transform CLI flags to compose configuration.
TypeScript Playground
TypeScript playground online. Write TypeScript and see the compiled JavaScript output in real-time.
SVG to React Component
Convert SVG to React component online. Transform SVG markup to a reusable React JSX component.
JSON Prettifier
Prettify and format JSON online. Free JSON beautifier with syntax highlighting and indentation.
CSS Formatter
Format and beautify CSS online. Free CSS formatter with proper indentation and line breaks.
XML Formatter Online
Format and prettify XML online. Free XML beautifier with proper indentation and tree structure.
HTML to React Converter
Convert HTML to React components online. Free HTML to JSX converter with className, style objects, and component wrapping.
CSV to JSON Online
Convert CSV to JSON online. Free CSV to JSON converter with auto-detect delimiter and header row parsing.
Chmod Visualizer
Interactive chmod permission calculator. Convert between symbolic and numeric Unix file permissions visually.
Text Diff Checker
Compare two texts and highlight differences online. Free diff tool with line-by-line and word-level comparison.
JSON to TypeScript Online
Convert JSON to TypeScript interfaces online. Free JSON to TS type generator with nested types and optional fields.
Base64 Encoder Decoder
Encode and decode Base64 strings online. Free Base64 encoder/decoder tool with file support.
Markdown to HTML Converter
Convert Markdown to HTML online. Free Markdown to HTML converter with live preview.
RGB to HEX Converter
Convert RGB colors to HEX online. Free RGB to HEX color converter with color picker.
HEX to RGB Converter
Convert HEX colors to RGB online. Free HEX to RGB color converter with live preview.
JSON Validator Online
Validate JSON syntax online. Free JSON validator with error detection, line numbers, and detailed error messages.
URL Encode/Decode Online
Encode and decode URLs online. Free URL encoder and decoder for query strings, paths, and special characters.
TypeScript to JavaScript Converter
Convert TypeScript code to JavaScript by removing type annotations, interfaces, enums, and generics. Free online TS to JS converter.
Color Contrast Checker
Check WCAG color contrast ratio
ASCII Table Generator
Generate ASCII art tables from data online. Create plain text tables for documentation, README files, and terminal output.
Number Base Converter
Convert numbers between bases online: binary, octal, decimal, hexadecimal, and custom bases. Multi-base conversion tool.
CSS Triangle Generator
Generate CSS triangles using borders. Create triangles pointing up, down, left, right, and diagonal with custom size and color.
IP Subnet Calculator
Calculate IP subnet masks, network addresses, broadcast addresses, and host ranges online. Supports IPv4 CIDR notation.
Markdown Link Checker
Check and validate links in Markdown documents. Find broken links, relative paths, and malformed URLs in your markdown files.
HTTP Headers Reference
Complete HTTP headers reference guide. Request and response headers explained with examples, security headers, CORS headers, caching headers.
String Utilities
Online string manipulation tools: reverse, capitalize, slug-ify, camelCase, snake_case, count occurrences, remove duplicates, and more.
Character Counter
Count characters, words, sentences, paragraphs, and estimate reading time. Free online text analysis tool.
Pixel to REM Converter
Convert pixels to REM and EM units online. Set custom base font size for accurate CSS unit conversions.
Email Validator Online
Validate email addresses online. Check email format, syntax, and domain. Supports batch email validation.
Crontab Validator
Validate and explain cron expressions. See next 5 run times, human-readable descriptions, and use common presets.
.gitignore Generator
Generate .gitignore files for Node.js, Python, Java, Go, React, Next.js, macOS, Windows, and more.
JSON to MySQL Schema
Convert JSON objects to MySQL CREATE TABLE statements. Auto-detect field types, add timestamps, and export SQL.
SVG to PNG Converter
Convert SVG files to PNG images online. Set custom dimensions, scale factor, and download instantly.
JSON Minifier Online
Compress and minify JSON data. Remove whitespace to reduce file size.
Base64 Image Encoder
Convert images to Base64 and Base64 to images
JavaScript Obfuscator Online
Obfuscate and protect JavaScript code. Free browser-based JS obfuscator.
HTML Encoder Online
Encode and decode HTML entities. Convert special chars to &, <, > online.
Python Formatter Online
Format Python code to PEP 8 standards. Learn about Black, autopep8, and ruff.
SHA256 Hash Online
Generate SHA-256 hashes instantly in your browser. Free online SHA256 calculator.
URL Encoder Online
Encode and decode URLs and query strings. Free percent-encoding tool.
CSS Beautifier
CSSコードを整形
HTTPヘッダーチェッカー
HTTPヘッダーを確認
IPアドレス検索
IPアドレスを検索
色覚シミュレーター
色覚異常をシミュレート
Cron式変換
Cron式を日本語に変換
テキスト差分ツール
テキストを比較
SQL フォーマッター
SQLクエリを整形
Strong Password Generator
Generate strong, secure passwords with customizable length and character types. Free online strong password creator.
Random Password Generator
Generate random passwords instantly with customizable options. Free online random password maker for secure accounts.
Secure Password Generator
Generate secure passwords with cryptographically strong random generation. Create hack-proof passwords for maximum security.
SAMLデコーダー
SAMLレスポンスとリクエストのデコードと検査
WiFi QRコード生成器
WiFiネットワーク共有用QRコードを生成
XPathテスター
XMLに対するXPath式のテストと評価
TOML ↔ JSON コンバーター
TOMLとJSON形式間の変換
Protobufデコーダー
Protocol Buffersバイナリデータのデコード
AIトークンカウンター
トークン数をカウントしAPIコストを見積もり
Certutil Base64 Decoder
Decode certutil Base64 encoded strings and certificates online. Convert Base64 from environment variables, certificates, and command-line output.
JS to TSX Converter
Convert JavaScript and JSX files to TypeScript TSX with automatic type annotations and React type inference.
JSON to JSON Schema Generator
Generate JSON Schema from JSON data automatically. Create Draft-07 compliant schemas with type inference and validation rules.
TOML Validator & Formatter
Validate and format TOML configuration files online. Check syntax, find errors, and beautify TOML with instant feedback.
CSS Nesting Converter
Convert flat CSS to native CSS nesting syntax and check browser support. Transform SCSS/SASS nesting to native CSS nesting.
Favicon Checker & Generator
Check if a website has proper favicons configured. Generate favicon HTML tags for all platforms including Apple Touch Icon and PWA manifest.
JSON Schema バリデーター
JSON Schemaを使用してJSONデータを検証。型チェック、必須フィールド、パターンマッチングなど
HTTPステータスコード検索
すべてのHTTPステータスコード（1xx-5xx）を検索・閲覧。詳細な説明、使用例、解決策を含む
QRコードジェネレーター
Generate QR codes from text, URLs, and data
CSS Border Radiusジェネレーター
Visual CSS border-radius generator with presets and live preview
TOML Editor
TOML editor, validator and JSON converter
エポックコンバーター
Unixエポックタイムスタンプと人間が読める日付を相互変換
JSON to Swift
Convert JSON to Swift Codable structs
GraphQLフォーマッター
GraphQLクエリをフォーマットして美化
JSON to PHP
Convert JSON to PHP arrays/classes
HTML to Pug
HTMLをPug (Jade) テンプレートに変換
YAML to TOML
YAMLとTOML形式の相互変換
TypeScript to Zod
TypeScript型をZodスキーマに変換
SQL to MongoDB
SQLクエリをMongoDBに変換
.env to JSON
.envとJSON形式の相互変換
正規表現を英語に
正規表現を英語で説明
JSON to HTMLフォーム
JSONからHTMLフォームを生成
JSON to GraphQL Schema
Convert JSON to GraphQL types
CSS Variables Generator
Generate CSS custom properties visually
OpenAPI to TypeScript
Convert OpenAPI schemas to TypeScript
Base32 Encoder/Decoder
Encode/decode Base32 strings
JSON to SQL
Convert JSON data to SQL INSERT statements
SCSS to CSS
Convert SCSS/Sass to plain CSS
Diff Viewer
Compare text with visual diff highlighting
API Tester
Test REST API endpoints in your browser
Hex to Text
Convert between hex strings and text
Color Gradient Generator
Visual CSS gradient generator
JSON to Scala
Convert JSON to Scala case classes
ASCII to Hex
Convert between ASCII text and hex
Binary to Text
Convert between binary and text
HTML Live Preview
Live HTML/CSS/JS editor with preview
Text to Morse Code
Convert text to Morse code and back
XML to CSV
Convert XML data to CSV format
IP Geolocation Lookup
Look up IP address geolocation
PNG to JPG
Convert images between PNG and JPG
Base58 Encoder/Decoder
Encode and decode Base58 strings
CSS Selector Tester
Test CSS selectors against HTML
cURL からコードへのコンバーター
cURL コマンドをコードに変換
JSON to Rust Struct
Convert JSON data to Rust struct definitions with serde support
TOML to YAML Converter
Convert TOML configuration files to YAML format
SVG to CSS Converter
Convert SVG to CSS background-image data URI
Cron Job Generator
Interactive cron expression builder
CSS Units Converter
Convert between CSS units
JSON to Protobuf
Convert JSON to Protocol Buffer definitions
Tailwind to CSS Converter
Convert Tailwind classes to vanilla CSS
YAML Formatter
Format and beautify YAML
Unix タイムスタンプ変換
Convert between Unix timestamps and human-readable dates
Text to ASCII Art
Convert text to ASCII art with various font styles
CSS Shadow Generator
Visual box-shadow and text-shadow generator
Regex Visualizer
Visual regex tester with match highlighting
Crontab Editor
Visual crontab editor with next run times
SQL to JSON Schema
Convert SQL CREATE TABLE to JSON schema
YAML Editor
YAML editor with validation and JSON conversion
HTTP Method Tester
Test HTTP requests with custom headers and body
Markdown to PDF
Preview Markdown as styled print-ready output
Tailwind CSS Converter
Convert CSS to Tailwind classes
SVG Editor
Edit and preview SVG code
JavaScript Obfuscator
Obfuscate JS code for protection
CSS Clip Path Generator
Visual clip-path shape generator
XML Validator
Validate XML syntax
CSP Header Generator
Build Content Security Policy headers
ENV File Editor
.env editor with export
CSS Filter Generator
Visual CSS filter generator
Nginx Config Generator
Generate Nginx configurations
Dockerfile Generator
Generate Dockerfiles visually
CSS Transition Generator
Visual CSS transition builder
API Response Generator
Generate mock API responses
HTML Entity Decoder
Encode/decode HTML entities
CSS Flexbox Playground
Interactive flexbox layout builder
JSON to CSV Online
Convert JSON to CSV format
JSON to Rust Serde
Convert JSON to Rust structs
CSS Text Shadow Generator
Visual text-shadow generator
JSONPath Evaluator
Evaluate JSONPath expressions
Webhook Tester
Test and inspect webhooks
画像リサイズツール
Resize images online for free with custom dimensions
画像トリミングツール
Crop images online for free with custom areas
WebP変換ツール
Convert images to and from WebP format
グラスモーフィズムCSSジェネレーター
Generate glassmorphism CSS effects with live preview
ニューモーフィズムCSSジェネレーター
Generate neumorphism soft UI CSS effects
アスペクト比計算機
Calculate and convert aspect ratios
XMLサイトマップジェネレーター
Generate XML sitemaps for your website
HTMLからテキスト変換
Convert HTML to plain text
JSONキーソーター
Sort JSON keys alphabetically
CSSグラデーションテキストジェネレーター
Create gradient text effects with CSS
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完全レスポンシブ。デスクトップ、タブレット、モバイルで使用可能。