ZeroTool Workbench

ZeroTool

Private browser tools for everyday development.

Format JSON, decode tokens, generate keys, compare text, and transform data in your browser, without uploading your input.

141 browser toolsClient-side processingFour languages
Quick launch 141
JSON Formatter JSON & Data Base64 Encode / Decode Encoding Basic Auth Header Generator Crypto & Auth UUID Generator IDs & QR URL Encode / Decode Encoding

A quiet workspace for quick, single-purpose utilities.

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Tool directory

141
JSON & Data JSON Formatter Format, minify and validate JSON in your browser. Keeps big numbers exact, flags duplicate keys and converts JSON5 or JSONC with comments. Encoding Base64 Encode / Decode Encode text to Base64 or decode Base64 back to plain text. Crypto & Auth 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. IDs & QR UUID Generator Generate v4 UUIDs instantly — single or batch. Encoding URL Encode / Decode Encode or decode URL components and query strings. Text & Markdown Text Case Converter Convert text to UPPER, lower, Title, camelCase, snake_case, and more. Text & Markdown Markdown Preview Live Markdown editor with real-time HTML preview. Supports GFM tables, task lists, and code blocks. Text & Markdown 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 Markdown to Word Converter Convert Markdown to a Word .docx in your browser with heading styles, Word numbering, tables, task lists, footnotes and images. Your Markdown is not uploaded. Color Color Converter Convert colors between HEX, RGB, and HSL formats with a live color preview. Code & Types Regex Tester Test regular expressions in real time with match highlighting and capture group details. Crypto & Auth Hash Generator Generate MD5, SHA-1, SHA-256, SHA-384, and SHA-512 hashes from any text. DevOps & Time Timestamp Converter Convert Unix timestamps to human-readable dates and vice versa. Auto-detects seconds vs milliseconds. Crypto & Auth JWT Decoder Decode and inspect JWT header, payload, and signature. Highlights expiry status and timestamp claims. Text & Markdown Diff Checker Compare two texts line by line and highlight additions and deletions. Powered by LCS algorithm. Crypto & Auth Password Generator Generate cryptographically secure passwords. Customize length and character sets with entropy meter. IDs & QR QR Code Generator Make static QR codes for links, text, vCard or MECARD contacts, email, phone, SMS and locations. PNG with whole pixels per module, or SVG. DevOps & Time Cron Expression Parser Parse and explain cron expressions in plain English. Preview next 10 scheduled run times. Text & Markdown Lorem Ipsum Generator Generate Lorem Ipsum placeholder text instantly. Choose paragraph count and copy to clipboard. Text & Markdown Word & Character Counter Count words, characters, sentences, and paragraphs. Estimate reading and speaking time. DevOps & Time Chmod Calculator Calculate Linux file permissions interactively. Convert between numeric and symbolic notation. JSON & 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. JSON & 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 & Markdown Line Tools Remove duplicate lines, sort alphabetically or numerically, reverse, shuffle, and trim text lines. Encoding Binary to Decimal & Hex Converter Convert binary, decimal, hex, octal and any base 2–36. Exact for large numbers, fractions and two's complement; points to the first bad digit. Code & Types SQL Formatter Format, beautify, and minify SQL queries with syntax highlighting. Image Aspect Ratio Calculator Calculate and resize aspect ratios. Lock ratio and scale dimensions proportionally. JSON & 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. JSON & Data TOML to JSON Converter Convert between TOML and JSON formats instantly with validation. Encoding Image to Base64 Converter Convert images to Base64, data URIs, CSS, HTML or Markdown, and Base64 back to images. The type comes from the file bytes; SVG can be URL-encoded. CSS CSS to Tailwind Converter Convert CSS properties to Tailwind utility classes instantly. CSS CSS Unit Converter Convert between px, rem, em, and vw CSS units instantly. Configurable root font size and viewport width. CSS CSS Specificity Calculator Calculate CSS selector specificity as (a, b, c) tuples. Compare multiple selectors, visual breakdown by ID, class, and element. Text & Markdown Markdown Table Generator Edit a GitHub-flavored Markdown table in a grid or paste it from Excel, Google Sheets, CSV, JSON or HTML. Pipes and line breaks are escaped; CJK columns line up. Code & Types JSON to TypeScript Generator Generate TypeScript interfaces from JSON. Handles nested objects, arrays, unions, and optional properties. IDs & QR Fake Data Generator Generate realistic test data: names, emails, addresses, UUIDs, and more. Export as JSON or CSV. Web & HTTP URL Parser Split a URL into scheme, host, port, path, query and fragment with your browser's parser, see what it changed and where RFC 3986 reads it differently, and edit parameters. Text & Markdown Slugify String Convert any text to a URL-friendly slug. Handles Unicode, removes special characters, custom separator support. Web & HTTP HTTP Status Codes Searchable reference for all HTTP status codes (1xx–5xx) with descriptions and use cases. Crypto & Auth HMAC SHA256 Generator Compute HMAC-SHA256, SHA-512, SHA-1 or MD5 from text, hex or Base64 keys, and check GitHub, Stripe, Slack, LINE, Feishu or DingTalk webhook signatures in your browser. Code & Types cURL to Code Converter Convert cURL commands to Python, JavaScript, Go, PHP, and Node.js code instantly. Code & Types JSON to Zod Schema Generate Zod validation schemas from JSON data. Handles nested objects, arrays, and optional properties. DevOps & Time Docker Run to Compose Convert docker run commands to docker-compose.yml. Supports ports, volumes, env vars, networks, and more. Crypto & Auth RSA Key Pair Generator Generate RSA key pairs (2048/4096-bit) in PEM or JWK format. Keys are generated in your browser and are not uploaded. Crypto & Auth TOTP Generator Generate RFC 6238 TOTP codes from a Base32 secret or otpauth:// URI, with countdown, previous and next codes, QR code, and a clock check. JSON & Data JSON Diff Compare two JSON objects and visualize differences. Outputs RFC 6902 JSON Patch and a color-coded tree diff. DevOps & Time Env File Parser Parse .env files online — visualize key-value pairs, detect errors, and export to JSON. Runs in your browser. JSON & Data YAML Validator Validate YAML syntax online — detailed error messages with line and column numbers, plus parsed structure preview. Runs in your browser. JSON & Data JSON Schema Validator Validate JSON, YAML or JSON Lines against a JSON Schema (draft-04 to 2020-12). Errors are grouped by data path and linked to the line and the schema keyword. Web & HTTP .htaccess Generator Generate Apache .htaccess configurations online. Force HTTPS, set caching, block directory listing, add custom redirects. Runs in your browser. Web & HTTP Robots.txt Generator Generate robots.txt files online. Configure user-agent rules, allow/disallow paths, and sitemap URLs. Runs in your browser. Image SVG to PNG Converter Convert SVG to PNG, JPEG or WebP in your browser. Scale or set exact pixels, keep transparency, convert many files into one ZIP. No upload. Image WebP Converter Convert PNG/JPG/GIF to WebP and WebP to PNG online. Batch conversion, quality control, file size comparison. Runs in your browser. CSS CSS Variables Generator Generate CSS custom properties from design tokens. Define colors, typography, spacing, and border radius — output ready-to-use :root variables. CSS CSS Grid Generator Build CSS Grid layouts visually. Set columns, rows, gaps, and template values with live preview and instant code output. JSON & Data JSONPath Tester Test JSONPath expressions against JSON data in real time. View matched results with syntax highlighting. Supports filters, wildcards, and recursive descent. CSS CSS Flexbox Generator Build CSS Flexbox layouts visually. Configure flex direction, wrap, justify-content, align-items, and gap with a live preview. JSON & 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. Crypto & Auth AES Encryption & Decryption Encrypt and decrypt text or files with AES-256-GCM in your browser. Use a password (PBKDF2, 600,000 iterations) or a raw 128/192/256-bit key. Nothing is uploaded. Code & Types JSON to Kotlin Data Class Generate Kotlin data classes from JSON. Handles nested objects, arrays, and nullable fields. Supports custom root class name. Code & Types JSON to Java POJO Generate Java POJO classes from JSON. Supports Jackson, Gson, and Lombok annotations. Handles nested objects and arrays. Code & Types JSON to Go Struct Generate Go structs with json tags from JSON. Handles nested objects, arrays, and nullable fields as pointers. Text & Markdown Fancy Text Generator Turn text into 23 Unicode fancy fonts — bold, italic, cursive, Fraktur, small caps, circled — and turn fancy text back into plain letters. Accents and emoji stay intact. Web & HTTP OpenAPI Validator Validate OpenAPI 3.0, 3.1, 3.2 and Swagger 2.0 (YAML or JSON) with line numbers: official schemas, $ref across files, path parameters, security schemes and examples. Nothing is uploaded. Text & Markdown 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 Translator Translate text to 8-bit binary (UTF-8) and binary back to text. Reads spaced, continuous and bin() output; points to bad bits and invalid bytes. Encoding NATO Phonetic Alphabet Convert text to NATO phonetic alphabet codes (Alfa, Bravo, Charlie…). Supports letters and digits. Word and table output modes. Runs in your browser. Text & Markdown Text to ASCII Art Generator Turn text into FIGlet ASCII art banners with 12 fonts. Output matches the figlet command line; set spacing and width, copy as code comments or Markdown, download TXT or PNG. Web & HTTP IP Subnet Calculator Calculate IPv4 subnet details from IP + CIDR. Outputs network address, broadcast, first/last host, usable hosts, subnet mask, and wildcard mask. Runs in your browser. Code & Types 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. Runs in your browser. JSON & 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. Runs in your browser. Code & Types SVG to JSX Converter Convert SVG to a React JSX component instantly. Handles camelCase attributes, className, xmlns cleanup. Optional TypeScript, forwardRef, and memo wrapping. Runs in your browser. JSON & Data Protobuf to JSON Decode Protobuf binary (hex, Base64, gRPC frames) to ProtoJSON with or without a .proto schema, encode JSON back to bytes and print sample JSON. Runs in your browser. Crypto & Auth htpasswd Generator Generate htpasswd lines for Apache and Nginx in bcrypt $2y$, SHA-512 crypt, APR1 and legacy formats, see which servers read each format, and check a password against an existing htpasswd file. Hashing runs in your browser. CSS 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. Color Color Shades Generator Turn one color into an 11-step 50–950 shade scale in OKLCH. Your color stays exact at its step, each step shows WCAG contrast, and the scale exports to CSS, Tailwind v3/v4, SCSS or JSON. IDs & QR ULID Generator Generate ULIDs (Universally Unique Lexicographically Sortable Identifiers). Single or batch (up to 100). Shows timestamp and random components. Built-in ULID decoder. Runs in your browser. IDs & QR QR Code Reader Read QR codes from an image, a pasted screenshot or your camera. Several codes per image, the real host of each link, Shift_JIS and GBK text. Runs in your browser. Code & Types TypeScript to Zod Schema Convert TypeScript interfaces and type aliases to Zod validation schemas. Handles unions, optional fields, arrays, nested objects, and enums. Runs in your browser. Code & Types JSON to Python Dataclass Generate Python dataclasses from JSON. Supports @dataclass, Pydantic v2 BaseModel, and TypedDict. Handles nested objects, arrays, and optional fields. Crypto & Auth JWT Generator / Signer Generate and sign JWT tokens (HS256, HS384, HS512) in your browser. Paste or edit header and payload JSON, set your secret, and copy the signed token. Code & Types JSON to Mongoose Schema Generate Mongoose schema definitions from JSON. Supports JavaScript and TypeScript output, timestamps option, nested objects, and arrays. Runs in your browser. JSON & Data JSON to CSV Converter Convert JSON arrays to CSV instantly. Supports nested object flattening (dot-path), custom delimiters, and RFC 4180 escaping. Runs in your browser. JSON & 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. Crypto & Auth Bcrypt Generator & Checker Generate and check bcrypt hashes in your browser. Pick $2b$, $2y$ or $2a$ and a cost from 4 to 31, see the 72-byte limit, and find out which of PHP, Laravel, Node.js, Python, Go and Spring accept a hash. Text & Markdown 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. Runs in your browser. CSS Glassmorphism CSS Generator Generate frosted-glass CSS or a Tailwind v4 utility. Preview local images, estimate text contrast, and include opaque fallbacks and reduced-transparency rules. CSS 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. CSS 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. IDs & QR 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. Runs in your browser. Web & HTTP Cookie Parser & Decoder Read a Cookie header, Set-Cookie lines or cookies.txt: decoded values, which cookies a browser keeps or rejects and why, the next request's Cookie header, and a redacted copy. CSS CSS Clip-Path Generator Build CSS clip-path shapes by dragging polygon points or setting circle, ellipse and inset values. Keeps two decimals, supports arrow-key editing, and previews path(), shape() and reference boxes in your browser. Color Color Palette Generator Generate complementary, split-complementary, analogous, triadic, tetradic, square and monochromatic palettes from any CSS color on an HSL or OKLCH color wheel. Copy values or export CSS variables, SCSS, Tailwind or JSON. Text & Markdown String Escape / Unescape Escape and unescape strings for JSON, JavaScript, Java, C, Python, HTML, XML, CSV, SQL, regex and shell. Invalid escapes are reported with their position. JSON & Data JSON to XML Converter Convert JSON to XML and XML to JSON instantly. Customizable root element, pretty-print toggle, and real-time conversion. Runs in your browser, no upload required. JSON & 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. Runs in your browser. CSS 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. DevOps & Time 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. IDs & QR WiFi QR Code Generator Make a Wi-Fi QR code guests join in one scan: escaped name and password, WPA3-only and hidden options, 32-byte and password checks, PNG, SVG and a printable card. Image EXIF Metadata Viewer View and remove EXIF metadata from JPEG photos online — strip GPS, camera info, and timestamps in your browser. Runs in your browser, 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. Runs in your browser, 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. CSS Cubic Bezier Generator Visual editor for CSS cubic-bezier() easing curves. Drag control points, preview the animation live, and copy CSS / SCSS / Tailwind output. Runs in your browser. Web & HTTP 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. DevOps & Time 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. Runs in your browser. Text & Markdown 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. Runs in your browser. Color Image Color Palette Extractor Extract a color palette from an image with the share of each color. Same image, same palette; exact colors from flat graphics. Copy HEX, RGB, HSL or OKLCH, export CSS, Tailwind, JSON, GIMP .gpl or Adobe .ase. Color Color Blindness Simulator Simulate 8 types of color vision deficiency on images, screenshots and color palettes. Compare all types side by side, save full-size PNGs and find color pairs that look the same. Runs in your browser; images are not uploaded. DevOps & Time Timezone Converter Convert any time across IANA timezones with automatic DST handling. Compare multiple zones side by side and share results via link. Runs in your browser. Text & Markdown AI Token Counter Count tokens with the exact OpenAI (o200k_base, cl100k_base) and DeepSeek V4 tokenizers in your browser, see every token, and estimate GPT, Claude, Gemini and DeepSeek API cost. Web & HTTP 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. Runs in your browser. Image SVG Optimizer Compress SVG with SVGO 4.1 in your browser: many files to one ZIP, a pixel check of the result and notes on removed IDs, classes or viewBox. No upload. Crypto & Auth PKCE Generator Generate an RFC 7636 PKCE code_verifier and S256 code_challenge, check why a challenge does not match, and build the authorization URL and token cURL. Nothing leaves the browser. Crypto & Auth SSL Certificate Decoder Decode X.509 certificates and whole chains from PEM, Base64, DER or PKCS #7: SANs, validity, key, extensions, SCTs and fingerprints, plus chain order and signature checks. Crypto & Auth File Hash Checker Get the SHA-256, SHA-1, SHA-384, SHA-512, MD5 or CRC32 of local files of any size and check them against a hash or a SHA256SUMS list. Files stay on your device. Image Image Compressor Compress JPEG, PNG, and WebP images in your browser. Adjust quality, resize on the long edge, and shrink file size instantly. Runs in your browser, no upload. IDs & QR 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. Runs in your browser. Code & Types HTML Minifier & Beautifier Minify or beautify HTML markup in your browser. Strip comments, collapse whitespace, or re-indent — instant, no upload, no signup. Web & HTTP 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 in your browser — files are not uploaded. Web & HTTP HAR Analyzer & Viewer Open a HAR file from Chrome, Firefox or Safari DevTools: sortable waterfall, request details and cURL, slow and failed requests, and a redacted copy without cookies or tokens. Color Color Picker from Image & Screen Pick a color from any pixel on your screen with the browser's native EyeDropper API (Chrome, Edge, Opera) or from an image or pasted screenshot. Get HEX, RGB, HSL, OKLCH and Display P3 that convert back to the same color, with wide-gamut and transparency warnings. Web & HTTP HTTP Header Analyzer Paste raw HTTP request or response headers and instantly inspect security, caching, CORS, content, and auth metadata. 88 header descriptions with compliance hints, JSON export. Runs in your browser. Code & Types GraphQL Formatter Format, beautify, minify, and validate GraphQL queries, mutations, and SDL schemas. Locate syntax errors with line and column. Runs in your browser, no upload. JSON & Data jq Playground Run jq 1.7.1 filters in your browser with -r, -s, -n, --arg and JSON Lines input. Output, stderr and exit codes match the jq command line; errors point to the bad spot. Code & Types 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. Runs in your browser. Text & Markdown Invisible Character Detector Find and remove zero-width spaces, BOMs, bidi controls and ASCII hidden in tag characters. Strip one category and keep emoji intact. Web & HTTP DNS Lookup Look up A, AAAA, CNAME, MX, TXT, NS, SOA, CAA, PTR and SRV records over DNS-over-HTTPS. Your browser asks Cloudflare or Google directly, with no ZeroTool server in between. Code & Types OpenAPI to TypeScript Generator Generate TypeScript interfaces from OpenAPI 3.0/3.1 specs in YAML or JSON. Supports $ref, oneOf/anyOf/allOf, enums, nullable, and optional Zod schemas. Runs in your browser. CSS CSS Clamp Calculator Generate responsive CSS clamp() values for fluid typography and spacing with live previews. Runs in your browser. IDs & QR Barcode Generator Generate EAN-13, EAN-8, UPC-A, Code 128, Code 39, and ITF-14 barcodes with automatic check digits. Download SVG or PNG, nothing uploaded. Crypto & Auth CSR Decoder Decode a PKCS#10 certificate signing request — Subject, public key, requested SANs and extensions — and verify its self-signature before you send it to a CA. Runs in your browser. Crypto & Auth Redact API Keys & Secrets Mask API keys, tokens, private keys and passwords in logs before pasting into AI chat, then restore them in the reply. JSON & Data SQLite Viewer Open .db / .sqlite files in your browser: browse tables, views and indexes, run SQL, export CSV. Nothing is uploaded. Image Pixelate Image Pixelate, blur or black out faces, text and secrets in any image or screenshot. Select areas or the whole image, strip metadata, no upload. Image GIF Splitter Split an animated GIF into PNG or JPG frames, download them as a ZIP, or build a sprite sheet with JSON. No upload. Image Sprite Sheet Generator Pack images, folders and GIF frames into one PNG or WebP sprite sheet with trim, padding and extrude. Export JSON for Phaser and PixiJS, XML or CSS. No upload. Image GIF Compressor Shrink animated GIFs in your browser with lossy compression, fewer colors, resizing and frame skipping. No upload. Image Image Splitter Split an image into grid tiles, an Instagram grid or a seamless carousel. Download PNG, JPG or WebP in a ZIP. No upload.

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