Privacy-First Utility Tools
Free, fast, and 100% private tools that run entirely in your browser. No server, no tracking, no data leaks.
JSON Tools
JSON Formatter & Validator
Free online JSON formatter and validator. Beautify, minify, and validate JSON data. 100% client-side processing - your data never leaves your browser.
JSON ↔ YAML converter
Convert between JSON and YAML in your browser with line/column errors. Data never leaves the device.
JSON to TypeScript
Turn a JSON sample into TypeScript interfaces or type aliases in your browser. Data stays on the device.
JSON Minifier
Remove whitespace from JSON and validate in one step—all in your browser. Focused workflow separate from prettifying.
JSONPath evaluator
Run JSONPath queries on JSON in your browser—view matching values or each match’s path. No upload.
XML formatter
Pretty-print or minify XML in your browser with DOMParser validation and a local serializer.
TOML formatter & validator
Format TOML and surface parse errors with @iarna/toml in your browser. Copy or download formatted.toml—local only.
.env file editor
Parse, validate, normalize, and merge .env files in your browser. Duplicate keys, POSIX hints, and export lines—copy or download locally.
INI / Java properties ↔ JSON
Convert INI or Java `.properties` text to JSON and back in your browser—sections, comments, and continuations parsed locally.
Converters
CSV to JSON / HTML / Markdown
Parse 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 & Decoder
Encode or decode URL components with encodeURIComponent / decodeURIComponent or encodeURI / decodeURI, and parse full URLs into parts — all locally in your browser.
HTML Entities
Escape and unescape HTML entities (&, <, numeric and named) in your browser — for snippets, attributes, and safe text.
Hex Encoder & Decoder
Convert text to UTF-8 hex and hex dumps back to text, with a byte view — all in your browser.
MIME Type Lookup
Search 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.
Unix timestamp converter
Convert Unix epoch seconds or milliseconds to UTC and local calendar time, or parse ISO and other date strings back to epoch — all in your browser.
Timezone converter
Compare IANA timezones for one instant: offsets, abbreviations, and local wall-clock strings using your browser’s Intl data — no network calls.
CSS Unit Converter & Fluid Type
Convert 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 Generator
Generate RFC 4122 version 4 UUIDs and the nil UUID in your browser. Batch up to 500 and copy in one click.
ULID Generator
Create sortable identifiers with an embedded millisecond timestamp. Decode any ULID to UTC, local time, and randomness.
NanoID Generator
Create 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 Generator
Generate cryptographically random passwords and tokens: pick character classes, exclude ambiguous symbols, require coverage, and batch up to 500 — all in your browser.
JWT Debugger
Encode (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 JSX
Optimize SVG with SVGO in a Web Worker, then turn it into a React component with camelCase attributes. Everything stays in your browser.
Cron Generator
Build and verify crontab schedules with a visual grid or raw expression. Human-readable explanations and next run times—all in your browser.
QR Code Studio
Create 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 Auditor
See what your browser exposes: hardware, WebRTC, canvas/WebGL/audio fingerprints, fonts, and screen — scored locally with no tracking.
Code Snap Studio
Turn 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 Calculator
IPv4/IPv6 subnet math: CIDR, masks, network and broadcast (IPv4), usable hosts, wildcard mask, binary view, and IP classification — 100% in your browser.
Password Strength & Entropy
Measure entropy, zxcvbn strength, and estimated crack times across hardware tiers — 100% offline in your browser.
Multi-Hash & Base64 Factory
Encode 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 Studio
Visual regex tester with live highlights, capture groups, explanations, and code snippets. Runs entirely in your browser.
SQL Formatter Studio
Format 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 Estimator
Compare 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 Studio
Generate RSA and ECC keys, build CSRs and self-signed certificates, and inspect PEM chains — all locally in your browser.
HMAC & Webhook Verifier
Generate and verify HMAC signatures (SHA-256, SHA-512, SHA-1, MD5) for webhook bodies — hex or Base64, entirely in your browser.
TOTP Tool
Generate 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 / decrypt
Encrypt or decrypt text and files with AES-128/192/256-GCM in your browser: paste hex key and IV, optional AAD, Web Crypto only.
RSA key generator
Generate RSA public/private key pairs in your browser with Web Crypto; export PKCS#8 private and SPKI public PEM.
PEM decoder
Split PEM text into labeled Base64 payloads and DER byte lengths in your browser — pairs with PKI and RSA tools.
HKDF & PBKDF2 playground
Derive keys from a passphrase or IKM with visible salt, info, iterations, and hash — Web Crypto in your browser.
Text Tools
Secret Share
Seal 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 Checker
Compare 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.
Text statistics
Count words, characters, lines, paragraphs, and rough sentences; estimate reading time from a configurable speed — all in your browser.
Text case converter
Turn phrases and identifiers into camelCase, PascalCase, snake_case, kebab-case, and CONSTANT_CASE using local heuristics — choose one phrase per box or one conversion per line — nothing is uploaded.
Slugify
Build URL- and file-friendly slugs from titles in your browser: Unicode-safe or Latin ASCII folding, hyphen or underscore separators, optional one-slug-per-line — nothing is uploaded.
Sort lines
Sort, reverse, or randomly shuffle lines from pasted text in your browser — optional locale-aware numeric sorting and case rules — nothing is uploaded.
Dedupe lines
Remove duplicate lines from pasted text in your browser — keep first occurrences or sort unique lines with locale-aware ordering — nothing is uploaded.
Find & Replace (batch)
Multiline find and replace in your browser — literal text (with optional case rules) or JavaScript regex with flags; replacement counts and copy — nothing is uploaded.
Lorem Ipsum generator
Create paragraphs, exact word counts, or Markdown-style bullet lists of placeholder Latin in your browser — tunable sentences, optional classic opening, regenerate with Web Crypto randomness — nothing is uploaded.
Whitespace normalizer
Normalize line endings (LF / CRLF), expand tabs to spaces or compress leading spaces to tabs, and strip trailing spaces — all in your browser with live stats — nothing is uploaded.
Levenshtein distance
Compare two strings with classic edit distance (insert, delete, substitute) and an optional dynamic-programming matrix — computed locally in your browser.
Markdown Studio
Live GFM Markdown editor with preview, auto-format, HTML export, and rich-text copy. 100% client-side.
Web Font & Typography Workbench
Pair heading and body fonts, build modular scales, tune variable axes, preview CLS-safe fallbacks, and export CSS — all in your browser.