All tools
Browse every LocalTools utility in one place. Each tool page includes related links and structured data so crawlers can discover the full set beyond the XML sitemap.
JSON Tools
Converters
- CSV to JSON / HTML / MarkdownParse CSV in your browser with auto-detected delimiters. Export as JSON (objects or arrays), sortable HTML tables, or GitHub-ready Markdown. Nothing is uploaded.
- URL Encoder & DecoderEncode or decode URL components with encodeURIComponent / decodeURIComponent or encodeURI / decodeURI, and parse full URLs into parts — all locally in your browser.
- HTML EntitiesEscape and unescape HTML entities (&, <, numeric and named) in your browser — for snippets, attributes, and safe text.
- Hex Encoder & DecoderConvert text to UTF-8 hex and hex dumps back to text, with a byte view — all in your browser.
- MIME Type LookupSearch a curated table of file extensions and MIME types. Filter by category, copy values, and see common extensions for a MIME string — all offline in your browser.
- CSS Unit Converter & Fluid TypeConvert px, rem, em, vh, vw, and %; build linear clamp() for fluid type; convert HEX, RGB, and HSL — all in your browser with live previews.
Developer Tools
- UUID GeneratorGenerate RFC 4122 version 4 UUIDs and the nil UUID in your browser. Batch up to 500 and copy in one click.
- ULID GeneratorCreate sortable identifiers with an embedded millisecond timestamp. Decode any ULID to UTC, local time, and randomness.
- NanoID GeneratorCreate compact, URL-friendly IDs with adjustable length and alphabet presets—or your own character set. Batch up to 500; all randomness stays local.
- Random String GeneratorGenerate cryptographically random passwords and tokens: pick character classes, exclude ambiguous symbols, require coverage, and batch up to 500 — all in your browser.
- JWT DebuggerEncode (sign) and decode JSON Web Tokens in the browser. Choose HMAC algorithm or unsigned tokens. 100% client-side — secrets never leave your device.
- SVG to JSXOptimize SVG with SVGO in a Web Worker, then turn it into a React component with camelCase attributes. Everything stays in your browser.
- Cron GeneratorBuild and verify crontab schedules with a visual grid or raw expression. Human-readable explanations and next run times—all in your browser.
- QR Code StudioCreate and scan QR codes for URLs, text, Wi-Fi, and contacts. Customize colors, error correction, and quiet zone. Export PNG, SVG, or WebP — all in your browser.
- Browser AuditorSee what your browser exposes: hardware, WebRTC, canvas/WebGL/audio fingerprints, fonts, and screen — scored locally with no tracking.
- Code Snap StudioTurn snippets into syntax-highlighted images (Carbon-style) for docs and social posts. Pick language, theme, window chrome, padding, and background — export PNG, SVG, or copy to clipboard, all locally.
- Subnet CalculatorIPv4/IPv6 subnet math: CIDR, masks, network and broadcast (IPv4), usable hosts, wildcard mask, binary view, and IP classification — 100% in your browser.
- Password Strength & EntropyMeasure entropy, zxcvbn strength, and estimated crack times across hardware tiers — 100% offline in your browser.
- Multi-Hash & Base64 FactoryEncode text to Base64, hex, URL, and HTML entities; compute SHA-256, SHA-512, SHA-1, and MD5 — all live in your browser. Drop a file for a local SHA-256 checksum.
- RegEx StudioVisual regex tester with live highlights, capture groups, explanations, and code snippets. Runs entirely in your browser.
- SQL Formatter StudioFormat SQL for PostgreSQL, MySQL, SQLite, and T-SQL, minify for production strings, and design CREATE TABLE scripts with a visual schema builder — all in your browser.
- Cloud Resource Cost EstimatorCompare AWS, Azure, and GCP compute SKUs against your target vCPU and RAM, model SSD/HDD/cold storage, and convert estimates into global currencies — instantly in your browser.
- PKI & Certificate StudioGenerate RSA and ECC keys, build CSRs and self-signed certificates, and inspect PEM chains — all locally in your browser.
- HMAC & Webhook VerifierGenerate and verify HMAC signatures (SHA-256, SHA-512, SHA-1, MD5) for webhook bodies — hex or Base64, entirely in your browser.
- TOTP ToolGenerate a TOTP secret, show an otpauth QR for authenticator apps, display the live code, and verify codes with Web Crypto — all locally.
- AES-GCM encrypt / decryptEncrypt or decrypt text and files with AES-128/192/256-GCM in your browser: paste hex key and IV, optional AAD, Web Crypto only.
Image Tools
Text Tools
- Secret ShareSeal text with AES-GCM and a master password. Share a single link where ciphertext and IV live in the URL hash — nothing is stored on a server.
- Diff CheckerCompare two texts with character, word, or line diff — side-by-side or inline. Ignore whitespace, swap sides, sync-scrolled panes. 100% local in your browser.
- Markdown StudioLive GFM Markdown editor with preview, auto-format, HTML export, and rich-text copy. 100% client-side.
- Web Font & Typography WorkbenchPair heading and body fonts, build modular scales, tune variable axes, preview CLS-safe fallbacks, and export CSS — all in your browser.