ZeroTool Workbench

ZeroTool

Private browser tools for everyday development.

Format JSON, decode tokens, generate keys, compare text, transform data, and keep every byte on your device.

130 browser toolsClient-side processingFour languages
Quick launch 130
JSON Formatter data Base64 Encode / Decode encoding Basic Auth Header Generator security UUID Generator dev URL Encode / Decode encoding

A quiet workspace for quick, single-purpose utilities.

Type a task, format, protocol, or file type.

Tool directory

130
Data JSON Formatter Prettify, minify, and validate JSON instantly in your browser. Encoding Base64 Encode / Decode Encode text to Base64 or decode Base64 back to plain text. Security Basic Auth Header Generator Generate and decode HTTP Basic Authentication headers in your browser. Copy Authorization headers, tokens, cURL snippets, and Fetch examples with no upload. Dev UUID Generator Generate v4 UUIDs instantly — single or batch. Encoding URL Encode / Decode Encode or decode URL components and query strings. Text Text Case Converter Convert text to UPPER, lower, Title, camelCase, snake_case, and more. Text Markdown Preview Live Markdown editor with real-time HTML preview. Supports GFM tables, task lists, and code blocks. Text Markdown Linter Check Markdown for style and formatting errors in real time. Shows rule IDs, line numbers, and clickable results. Runs entirely in-browser. Text Markdown to Word Converter Convert Markdown to Word (.docx) files instantly. Supports headings, bold/italic, lists, tables, code blocks, and more. Runs entirely in-browser — your document is never uploaded. Dev Color Converter Convert colors between HEX, RGB, and HSL formats with a live color preview. Dev Regex Tester Test regular expressions in real time with match highlighting and capture group details. Security Hash Generator Generate MD5, SHA-1, SHA-256, SHA-384, and SHA-512 hashes from any text. Dev Timestamp Converter Convert Unix timestamps to human-readable dates and vice versa. Auto-detects seconds vs milliseconds. API JWT Decoder Decode and inspect JWT header, payload, and signature. Highlights expiry status and timestamp claims. Text Diff Checker Compare two texts line by line and highlight additions and deletions. Powered by LCS algorithm. Security Password Generator Generate cryptographically secure passwords. Customize length and character sets with entropy meter. Dev QR Code Generator Generate QR codes from URLs, text, Wi-Fi credentials, and more. Download as PNG. Dev Cron Expression Parser Parse and explain cron expressions in plain English. Preview next 10 scheduled run times. Text Lorem Ipsum Generator Generate Lorem Ipsum placeholder text instantly. Choose paragraph count and copy to clipboard. Text Word & Character Counter Count words, characters, sentences, and paragraphs. Estimate reading and speaking time. Dev Chmod Calculator Calculate Linux file permissions interactively. Convert between numeric and symbolic notation. Data CSV to JSON Converter Convert CSV to JSON and JSON to CSV instantly. Handles quoted fields, auto-detects headers. Encoding HTML Entity Encoder / Decoder Encode and decode HTML entities. Supports named, decimal, and hex entities. Data YAML to JSON Converter Convert YAML to JSON and JSON to YAML instantly. Supports nested objects, arrays, and all YAML 1.2 features. Text Line Tools Remove duplicate lines, sort alphabetically or numerically, reverse, shuffle, and trim text lines. Dev Number Base Converter Convert between binary, octal, decimal, and hex number systems. Dev SQL Formatter Format, beautify, and minify SQL queries with syntax highlighting. Dev Aspect Ratio Calculator Calculate and resize aspect ratios. Lock ratio and scale dimensions proportionally. Data XML Formatter Format, beautify, and minify XML documents with syntax validation. Encoding ASCII Converter Convert between text and ASCII codes. Supports decimal, hex, and binary representations. Data TOML to JSON Converter Convert between TOML and JSON formats instantly with validation. Encoding Image to Base64 Converter Convert images to Base64 strings and Data URIs. Supports PNG, JPEG, GIF, and more. Dev CSS to Tailwind Converter Convert CSS properties to Tailwind utility classes instantly. Dev CSS Unit Converter Convert between px, rem, em, and vw CSS units instantly. Configurable root font size and viewport width. Dev CSS Specificity Calculator Calculate CSS selector specificity as (a, b, c) tuples. Compare multiple selectors, visual breakdown by ID, class, and element. Text Markdown Table Generator Build Markdown tables visually — add rows and columns, paste CSV or JSON, then copy the formatted table. Dev JSON to TypeScript Generator Generate TypeScript interfaces from JSON. Handles nested objects, arrays, unions, and optional properties. Dev Fake Data Generator Generate realistic test data: names, emails, addresses, UUIDs, and more. Export as JSON or CSV. Dev URL Parser Parse any URL into its components: protocol, host, port, path, query parameters, and hash. Instant browser-native parsing. Text Slugify String Convert any text to a URL-friendly slug. Handles Unicode, removes special characters, custom separator support. API HTTP Status Codes Searchable reference for all HTTP status codes (1xx–5xx) with descriptions and use cases. API HMAC Generator Generate HMAC signatures using SHA-256, SHA-384, or SHA-512. Hex and Base64 output. Runs entirely in your browser. API cURL to Code Converter Convert cURL commands to Python, JavaScript, Go, PHP, and Node.js code instantly. Dev JSON to Zod Schema Generate Zod validation schemas from JSON data. Handles nested objects, arrays, and optional properties. Dev Docker Run to Compose Convert docker run commands to docker-compose.yml. Supports ports, volumes, env vars, networks, and more. Security RSA Key Pair Generator Generate RSA key pairs (2048/4096-bit) in PEM or JWK format. 100% client-side — keys never leave your browser. API TOTP Generator Generate RFC 6238 TOTP codes with live countdown. Configurable algorithm, digits, and period. Includes QR code. Data JSON Diff Compare two JSON objects and visualize differences. Outputs RFC 6902 JSON Patch and a color-coded tree diff. Dev Env File Parser Parse .env files online — visualize key-value pairs, detect errors, and export to JSON. 100% client-side. Data YAML Validator Validate YAML syntax online — detailed error messages with line and column numbers, plus parsed structure preview. 100% client-side. API JSON Schema Validator Validate JSON data against a JSON Schema online. Supports Draft-07 and Draft 2020-12. Shows error paths and detailed messages. 100% client-side. Dev .htaccess Generator Generate Apache .htaccess configurations online. Force HTTPS, set caching, block directory listing, add custom redirects. 100% client-side. Dev Robots.txt Generator Generate robots.txt files online. Configure user-agent rules, allow/disallow paths, and sitemap URLs. 100% client-side. Image SVG to PNG Converter Convert SVG files to PNG online. Upload or paste SVG code, choose output size and background. 100% client-side Canvas API. Image WebP Converter Convert PNG/JPG/GIF to WebP and WebP to PNG online. Batch conversion, quality control, file size comparison. 100% client-side. Dev CSS Variables Generator Generate CSS custom properties from design tokens. Define colors, typography, spacing, and border radius — output ready-to-use :root variables. Dev CSS Grid Generator Build CSS Grid layouts visually. Set columns, rows, gaps, and template values with live preview and instant code output. Dev JSONPath Tester Test JSONPath expressions against JSON data in real time. View matched results with syntax highlighting. Supports filters, wildcards, and recursive descent. Dev CSS Flexbox Generator Build CSS Flexbox layouts visually. Configure flex direction, wrap, justify-content, align-items, and gap with a live preview. Data JSON to JSON Schema Paste JSON and instantly generate a JSON Schema draft-07. Infers types, required fields, and nested objects or arrays. Encoding Morse Code Translator Translate text to Morse code and Morse code back to text. Supports letters, numbers, and common punctuation. Security AES Encrypt / Decrypt Encrypt and decrypt text using AES-GCM with a user-supplied password. 100% client-side via Web Crypto API — nothing leaves your browser. Dev JSON to Kotlin Data Class Generate Kotlin data classes from JSON. Handles nested objects, arrays, and nullable fields. Supports custom root class name. Dev JSON to Java POJO Generate Java POJO classes from JSON. Supports Jackson, Gson, and Lombok annotations. Handles nested objects and arrays. Dev JSON to Go Struct Generate Go structs with json tags from JSON. Handles nested objects, arrays, and nullable fields as pointers. Text Unicode Text Converter Convert text to Unicode decorative styles: Bold, Italic, Script, Fraktur, Double-Struck, Circled, and more. One-click copy for each style. API OpenAPI Validator Validate OpenAPI 3.0 and 3.1 specs (YAML or JSON) online. Shows validation errors with paths, spec info, and endpoint counts. 100% client-side. Data CSV to Markdown Table Convert CSV to a Markdown table instantly. Supports quoted fields, auto-detects headers, and lets you choose left, center, or right column alignment. Encoding Text to Binary Converter Convert text to binary (UTF-8) and binary back to text. Supports spaced and continuous binary formats. 100% client-side. Encoding NATO Phonetic Alphabet Convert text to NATO phonetic alphabet codes (Alpha, Bravo, Charlie…). Supports letters and digits. Word and table output modes. 100% client-side. Text Text to ASCII Art Convert text to ASCII art using 12 figlet fonts (Standard, Doom, Slant, Shadow…). Font selector, instant preview, copy output. 100% client-side. Dev IP Subnet Calculator Calculate IPv4 subnet details from IP + CIDR. Outputs network address, broadcast, first/last host, usable hosts, subnet mask, and wildcard mask. 100% client-side. Dev HTML to JSX Converter Convert HTML to React JSX instantly in your browser. Handles className, htmlFor, inline style objects, camelCase events, self-closing tags, and comments. 100% client-side. Data CSV to SQL Converter Convert CSV data to SQL INSERT statements. Supports MySQL, PostgreSQL, SQLite dialects, batch and individual insert modes, NULL handling, proper escaping. 100% client-side. Dev SVG to JSX Converter Convert SVG to a React JSX component instantly. Handles camelCase attributes, className, xmlns cleanup. Optional TypeScript, forwardRef, and memo wrapping. 100% client-side. API Protobuf to JSON Convert .proto schema to sample JSON, or decode Protobuf binary data (hex/base64) to JSON. Supports proto3, nested messages, enums. 100% client-side. Security htpasswd Generator Generate Apache htpasswd password hashes online. Supports bcrypt (default), MD5 APR1, SHA1, and plaintext. Batch mode. All hashing is 100% client-side — passwords never leave your browser. Dev CSS Box Shadow Generator Generate CSS box-shadow values visually. Adjust horizontal offset, vertical offset, blur, spread, opacity, color, and inset mode with sliders. Live preview and one-click copy. Dev Color Shades Generator Generate 10 Tailwind-style color shades (50–900) from any base color. Shows HEX, HSL, and RGB values. Click to copy individual shades or copy all as CSS variables. Dev ULID Generator Generate ULIDs (Universally Unique Lexicographically Sortable Identifiers). Single or batch (up to 100). Shows timestamp and random components. Built-in ULID decoder. 100% client-side. Dev QR Code Decoder Decode QR codes from images or camera. Supports URLs, text, vCard, WiFi. 100% client-side. Dev TypeScript to Zod Schema Convert TypeScript interfaces and type aliases to Zod validation schemas. Handles unions, optional fields, arrays, nested objects, and enums. 100% client-side. Dev JSON to Python Dataclass Generate Python dataclasses from JSON. Supports @dataclass, Pydantic v2 BaseModel, and TypedDict. Handles nested objects, arrays, and optional fields. API JWT Generator / Signer Generate and sign JWT tokens (HS256, HS384, HS512) entirely in your browser. Paste or edit header and payload JSON, set your secret, and copy the signed token. Dev JSON to Mongoose Schema Generate Mongoose schema definitions from JSON. Supports JavaScript and TypeScript output, timestamps option, nested objects, and arrays. 100% client-side. Data JSON to CSV Converter Convert JSON arrays to CSV instantly. Supports nested object flattening (dot-path), custom delimiters, and RFC 4180 escaping. 100% client-side. Data YAML to TOML Converter Convert YAML to TOML and TOML to YAML instantly. Handles nested objects, arrays, and all common data types. Free, browser-based, no upload required. Security Bcrypt Generator Generate and verify bcrypt password hashes online. Adjustable cost factor (4–14), Web Worker-powered to keep UI responsive. 100% client-side — passwords never leave your browser. Text HTML to Markdown Converter Convert HTML to Markdown instantly in your browser. Preserves headings, bold, italic, links, images, code blocks with language tags, GFM tables, and nested lists. 100% client-side. Dev Glassmorphism CSS Generator Generate glassmorphism CSS effects visually. Adjust blur, saturation, background opacity, border, border-radius, and box-shadow with live preview. Outputs backdrop-filter + -webkit-backdrop-filter. 100% client-side. Dev CSS Triangle Generator Generate CSS triangles in any direction using the border hack. Pick direction, size, and color — get ready-to-use CSS code instantly. Free online css triangle generator online. Dev CSS Gradient Generator Generate CSS gradients visually. Linear, radial, and conic types. Adjust angle, position, and up to 6 color stops with live preview and instant copy. Free online gradient generator. Dev Nano ID Generator Generate Nano IDs with customizable size (1–128) and alphabet: URL-safe, alphanumeric, hex, numbers-only, or custom. Single or batch up to 100. 100% client-side. Dev Cookie String Parser Parse Cookie header strings into a table of name/value pairs. Identifies flags (HttpOnly, Secure, SameSite, Path, Domain, Expires, Max-Age). URL decode toggle. Copy as JSON. 100% client-side. Dev CSS Clip-Path Generator Generate CSS clip-path shapes visually. Drag handles to create polygons, circles, ellipses, and inset shapes. Includes presets (hexagon, star, arrow, diamond, triangle) with live preview and instant copy. Free online clip-path generator. Color Color Palette Generator Generate complementary, analogous, triadic, and tetradic color palettes from any base color. Enter HEX or pick a color to instantly see 4 harmonious palettes. Click to copy individual colors or copy all HEX values per palette. 100% browser-based. Text String Escape / Unescape Escape and unescape strings for JavaScript, JSON, and HTML Entities. Supports escape sequences including newline, tab, Unicode, and hex. Real-time processing. 100% client-side. Data JSON to XML Converter Convert JSON to XML and XML to JSON instantly. Customizable root element, pretty-print toggle, and real-time conversion. 100% client-side, no upload required. Data JSONL Converter Convert JSONL/NDJSON to JSON arrays and JSON arrays back to JSON Lines. Validate each line, locate parse errors, and export valid records. 100% client-side. Dev CSS Filter Generator Generate CSS filter effects visually. Adjust blur, brightness, contrast, grayscale, hue-rotate, invert, opacity, saturate, and sepia with sliders. Live preview with custom image upload. Free online CSS filter generator. Dev Cron Job Generator Build cron expressions visually with field-by-field controls. Choose every, every-N, range, or specific values for minute, hour, day, month, and weekday. Shows human-readable description and next 10 run times. Dev WiFi QR Code Generator Generate QR codes that connect devices to your Wi-Fi instantly. Enter SSID, password, and encryption — guests scan to join. 100% client-side. Image EXIF Metadata Viewer View and remove EXIF metadata from JPEG photos online — strip GPS, camera info, and timestamps in your browser. 100% client-side, no upload. Image Favicon Generator Generate a complete favicon set from emoji, text, image, or SVG. Outputs ICO, multi-size PNGs, apple-touch-icon, and manifest. 100% client-side, no upload. Color Color Contrast Checker Check WCAG color contrast ratio for any foreground and background. Get AA/AAA pass-fail for body text, large text, and UI components, plus a one-click "keep hue, fix lightness" suggestion when contrast is too low. Dev Cubic Bezier Generator Visual editor for CSS cubic-bezier() easing curves. Drag control points, preview the animation live, and copy CSS / SCSS / Tailwind output. 100% browser-based. Dev Meta Tag Generator Build a complete <head> block — Open Graph, Twitter Card, Schema.org JSON-LD, and SEO basics — with live previews for Google, Facebook, Twitter, and Discord. 100% client-side. Dev Gitignore Generator Build a .gitignore file from 200+ official github/gitignore templates. Pick languages, frameworks, IDEs, and OS, merge with deduplication, then download or copy. 100% client-side. Text Markdown TOC Generator Build a clickable table of contents from Markdown headings. Supports GitHub, GitLab, Jekyll, and Bitbucket anchor styles, heading-level filtering, and in-place TOC updates via <!-- toc --> markers. 100% client-side. Image Image Color Palette Extractor Extract dominant colors from any image with k-means clustering. HEX, RGB, HSL, OKLCH, plus CSS variables and Tailwind config. 100% client-side. Color Color Blindness Simulator Simulate 8 types of color vision deficiency on any color or image. See protanopia, deuteranopia, tritanopia, and more side by side. 100% client-side, no upload. Dev Timezone Converter Convert any time across IANA timezones with automatic DST handling. Compare multiple zones side by side and share results via link. 100% browser-based. Dev AI Token Counter Count tokens and estimate costs for GPT-5, GPT-4.1, Claude Sonnet 4.6, Gemini 3, Llama 3.3, and DeepSeek V3 in your browser. No upload, no API key. Security CSP Header Generator Build a Content-Security-Policy header from directives, hosts, hashes, and nonces. Strict-mode templates with report-only fallback, plus Express and Nginx snippets. 100% client-side. Image SVG Optimizer Minify SVG files in your browser with SVGO — toggle plugins, compare byte savings, copy or download the cleaned markup. No upload. Security PKCE Generator Generate OAuth 2.0 / 2.1 PKCE code_verifier and code_challenge pairs (S256 + plain). Cryptographically secure via SubtleCrypto, with authorization URL and cURL preview. 100% client-side. Security SSL Certificate Decoder Decode X.509 PEM certificates instantly — view Subject, Issuer, validity, SANs, public key, signature algorithm, and SHA-256/SHA-1/MD5 fingerprints. 100% client-side. Security File Hash Checker Compute SHA-256, SHA-1, SHA-384, SHA-512, and MD5 checksums of any local file in your browser. No upload — verify download integrity privately and compare against an expected hash. Image Image Compressor Compress JPEG, PNG, and WebP images in your browser. Adjust quality, resize on the long edge, and shrink file size instantly. 100% local — no upload, no tracking. Dev IBAN Validator & Parser Validate any IBAN with mod-97 checksum and parse it into country, check digits, bank code, branch code, and account number. Covers 80+ countries from the SWIFT IBAN Registry. 100% client-side. Dev HTML Minifier & Beautifier Minify or beautify HTML markup in your browser. Strip comments, collapse whitespace, or re-indent — instant, no upload, no signup. API MIME Type Lookup Find the exact MIME type for any file extension and reverse-search by Content-Type. Includes a magic-bytes sniffer that detects file type 100% in your browser — files never uploaded. Dev HAR File Analyzer Drop a HAR file from your browser DevTools and visualize the request waterfall, status codes, headers, cookies, and bottlenecks. 100% client-side, no upload. Color Eyedropper Color Picker Pick colors from anywhere on your screen using the browser's native EyeDropper API. Output sRGB HEX, RGB, and HSL with one click, save a recent palette in your browser — no upload, no extension. Falls back to a native color picker when EyeDropper is unavailable. API HTTP Header Analyzer Paste raw HTTP request or response headers and instantly inspect security, caching, CORS, content, and auth metadata. 100+ header descriptions with compliance hints, JSON export. 100% client-side. Dev GraphQL Formatter Format, beautify, minify, and validate GraphQL queries, mutations, and SDL schemas. Locate syntax errors with line and column. 100% client-side, no upload. Data jq Playground Test jq filters against JSON in your browser with the official jq 1.7 engine. Pipe, select, map, group_by, sort, reduce — no upload, no install. Dev JavaScript Keycode Explorer Press any key in your browser to instantly see event.key, event.code, keyCode, charCode, location, repeat, and modifier states — plus a ready-to-copy JS snippet. 100% client-side. Text Zero-Width Character Detector Detect and strip invisible Unicode characters from text — zero-width spaces, BOM, bidi marks, tag characters used as ChatGPT watermarks. 100% client-side. API DNS Lookup Look up A, AAAA, CNAME, MX, TXT, NS, SOA, CAA, PTR, and SRV records via DNS-over-HTTPS. Cloudflare and Google resolvers, no server proxy. 100% client-side.

Built for local, fast work

Private by default

Inputs are processed in your browser, so sensitive snippets stay on the machine in front of you.

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Static Astro pages, tiny interactions, and direct routes keep each tool one click away.

Made for teams

English, Chinese, Japanese, and Korean pages share one catalog and one predictable layout.

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