開発
JSON・正規表現・CSV などの開発者向けツール
下のツールを選ぶだけで利用できます。すべて無料でブラウザ内で動作します。
💻 開発 · 計 66 個のツール
ASCII コード表ASCII table tool: lookup char decimal, hex and binary with search and copy for development and learning, with one-click copy, offline.
Base32 変換ツールBase32 converter tool: support Base32 encoding and decoding with padding and bulk for development, with one-click copy, offline.
Base64 画像プレビューBase64 image viewer: paste a Data URL or raw Base64 to preview the image locally with estimated size. Nothing is uploaded. Ideal for frontend debugging.
Brazil CPF ValidatorBrazil CPF validator: enter 11-digit CPF to validate for Brazil, multilingual.
Brazil PIX Key ValidatorBrazil PIX validator: enter CPF/CNPJ/email/phone/random key to validate PIX format for Brazil.
円錐グラデーションジェネレーターConic gradient generator: adjust angle, stops and center with live preview and CSS copy, animated for front-end gradien Supports batch processing and one-click copy.
クレジットカード番号検証Credit card validator: validate numbers with Luhn and detect Visa and Mastercard for payments and fraud prevention, with one-click copy and offline.
cron式ジェネレーターCron generator: visually pick minute/hour/day/month/week to build Cron, parse and preview next runs for scheduling and DevOps.
暗号資産アドレス検証Crypto address validator: validate BTC/ETH and multi-chain formats with checksum, chain hints and error tips before transfers.
CSSイージングジェネレーターCSS easing generator: visually adjust cubic-bezier curve to generate transition code with live preview for frontend and animation, with one-click copy and offline.
CSS 詳細度計算機CSS specificity calculator: enter any selector to get specificity a,b,c with priority and override explanation for frontend debugging, one-click copy and offline.
CSS単位コンバーターCSS units converter: convert px, rem, em, vw/vh and % by base font with responsive preview for front-end layouts. Supports batch processing and one-click copy.
CSV → JSON 変換CSV to JSON converter: convert tabular data to JSON array with delimiters and header detection for data, with one-click copy and offline.
CSV テーブルプレビューCSV viewer: paste CSV data to parse as table supporting comma, semicolon and Tab with quoted fields for data viewing and cleaning, with one-click copy and offline.
HTTP リクエスト → curl 変換cURL converter: generate cURL commands from method, URL, headers and body with import for API debugging, with one-click copy and offline.
curl を HTTP リクエストに変換cURL to HTTP parser: paste cURL to get method, URL, headers and body with highlighting and copy for API debugging and d Supports batch processing and one-click copy.
メールアドレス検証Email validator: check length, username and domain labels with clear tips per RFC for registration, with one-click copy and offline.
EU VAT Number ValidatorEU VAT number validator: enter VAT number to validate format with country prefix.
Excel 列名と番号の相互変換Excel column name converter: convert between letters and numbers A1 AB28 XFD16384 bidirectionally with batch for spreadsheets, with one-click copy and offline.
Excel 数式ジェネレーターExcel formula generator: pick function type and fill parameters to generate copy-ready formulas with examples for spreadsheets, with one-click copy and offline.
ファイルハッシュ計算機File hash calculator: compute SHA-1 and SHA-256 checksums of files locally for privacy for verification and security, with one-click copy and offline.
ファイル → Base64File to Base64: upload any file to generate Base64 and Data URL with image preview and copy for front-end embedding and API debugging.
FlexboxレイアウトジェネレーターFlexbox generator: adjust direction, alignment and gap with live preview and CSS copy for front-end flex layouts and responsive design.
Git コマンド早見表Git cheatsheet: pick a scenario (init, commit, branch, remote, undo, merge, log) for common commands with one-click copy. Runs locally.
Git コミットメッセージ生成ツールGit commit message generator: generate Conventional Commits messages with type and scope for development and collaboration, with one-click copy and offline.
HEX ダンプツールHex dump viewer: upload file or paste text to get hex and ASCII view with offset, width and search for reverse engineering and debugging.
hreflangタグジェネレーターHreflang generator: generate alternate link tags for multilingual sites with validation for SEO, with one-click copy and offline.
HTML エンティティ変換ツールHTML entities converter: encode special characters to HTML entities or decode back with preview for web, with one-click copy and offline.
HTML 整形ツールHTML formatter: paste HTML to beautify or minify with highlighting and error hints for front-end and code cleanup. Supports batch processing and one-click copy.
HTML リアルタイムプレビューHTML preview: paste HTML/CSS/JS for live rendered preview with split view and copy for front-end debugging and template Supports batch processing and one-click copy.
HTML → JSXHTML to JSX: transforms HTML snippets to React JSX handling class and style. For frontend. Supports batch processing, export and one-click copy, offline use.
HTML からテキストへの変換ツールHTML to text: extract text from HTML preserving paragraphs with tag stripping and entity decoding for content cleaning. Supports batch processing and one-click copy.
HTTP メソッド早見表HTTP methods reference: explains GET, POST, PUT, PATCH, DELETE usage and idempotency. Supports batch processing, export and one-click copy, offline use.
IBAN 検証ツールIBAN validator: validate country code length and mod-97 checksum for international transfers, with one-click copy and offline.
India PAN ValidatorIndia PAN validator: enter 10-character PAN to validate format for India.
Japan Invoice Number ValidatorJapan invoice number validator: enter 13-14 digit registration number to validate for Japan.
Japan My Number ValidatorJapan My Number validator: enter 12-digit number to validate checksum for Japan.
JSON 比較ツールJSON diff tool: paste two JSON documents to find added, removed and changed paths with highlighting for API and config comparison, with one-click copy and offline.
JSON 整形/圧縮/検証JSON formatter: paste JSON to beautify, minify and validate with highlighting and error location for dev debugging. Supports batch processing and one-click copy.
JSON 整形・検証・圧縮ツールJSON formatter: beautify, validate and minify to single line with custom indent and character count for development and debugging, with one-click copy and offline.
JSON マージツールJSON merge: merge multiple JSON objects with deep merge and conflict strategies for config and data integration. Supports batch processing and one-click copy.
JSON 圧縮・整形ツールJSON minifier and beautifier: compress or beautify JSON showing byte count and savings in real time for API debugging, with one-click copy and offline.
JSON パス検索JSON path query tool: enter JSON and dot-path with array indexes to extract values quickly with highlighting for API debugging, one-click copy and offline.
JSON Schema ジェネレーターJSON Schema generator: pastes sample JSON to auto generate JSON Schema with nested fields. Supports batch processing, export and one-click copy, offline use.
JSON → Markdown テーブルJSON to Markdown converter: convert object array to Markdown table with header and alignment for docs and README, with one-click copy and offline.
JSON → XMLJSON to XML converter: paste JSON to get well-formed XML with attribute and array handling, formatting and validation for integration.
CSSローダージェネレーターCSS loader generator: pick spinner, ring, dots or bars style with color, size and speed for instant preview and paste-ready CSS with keyframes.
Markdown オンラインエディタMarkdown editor: edit on left and preview on right supporting headings, lists and code blocks for writing and docs, with one-click copy and offline.
SEOメタタグジェネレーターMeta tags generator: enter title, description and keywords to generate SEO Meta and Open Graph tags for web optimizatio Supports batch processing and one-click copy.
Mexico CURP ValidatorMexico CURP validator: enter 18-character CURP to validate format for Mexico.
Mexico RFC ValidatorMexico RFC validator: enter RFC to validate format for Mexico SAT.
ニューモーフィズムジェネレーターNeumorphism generator: adjust shadow, radius and background with live preview and CSS copy for card and button design. Supports batch processing and one-click copy.
パスワードエントロピー計算機Password entropy calculator: analyze charset, length and entropy with crack time estimate for security, with one-click copy and offline.
ランダムパスワード生成器Random password generator: customize length and character types showing entropy for accounts, with one-click copy and offline.
PX・REM/EM 換算器PX to REM converter: convert px, rem and em based on root font size 16px for responsive and mobile styles, with one-click copy and offline.
README ジェネレーターREADME generator: enter project name, description, install and usage to generate standard Markdown README for open source and docs, with one-click copy and offline.
正規表現エスケープRegex escape tool: auto escape strings for regex with bulk and preview for development and text processing, with one-click copy, offline and multilingual.
正規表現テスターRegex tester: test regex against text with live highlighting and match count for development, with one-click copy and offline.
robots.txt ジェネレーターRobots.txt generator: create crawler rules with allow disallow, sitemap and validation for SEO and site management, with one-click copy, offline and multilingual.
バージョン比較ツールSemVer compare tool: compare two versions and parse major minor patch and prerelease for dev and release management, with one-click copy, offline.
サイトマップジェネレーターSitemap generator: create XML sitemap from URL list with priority and frequency for SEO and site management, with one-click copy, offline and multilingual.
JSON-LD構造化データジェネレーターStructured data generator: create JSON-LD by type with validation and preview for SEO and site management, with one-click copy, offline and multilingual.
テキスト差分チェッカーText diff tool: highlight differences between two texts with line and character diff for proofing and version compare, with one-click copy, offline.
CSS TransformジェネレーターTransform generator: visually generate CSS transform code with translate, rotate and scale preview for frontend and design, with one-click copy, offline.
User-AgentジェネレーターUser agent generator: create random UA for browsers and devices with custom and bulk for testing and crawling, with one-click copy, offline.
XML 整形XML formatter: beautify with indentation supporting comments and CDATA with validation for config, with one-click copy and offline.
よくある質問
「開発」カテゴリとは？
「開発」カテゴリには 66 個の無料ツールがあります。すべてブラウザ内で動作します。
これらのツールは無料ですか？
はい、すべて無料で回数制限もありません。
登録は必要ですか？
不要です。ページを開くだけで使えます。データはアップロードされません。
対応言語は？
This site supports 12 languages: Chinese, English, Japanese, Spanish, French, Portuguese, Arabic, Indonesian, Hindi, Thai, Vietnamese and Bengali.