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Compose device screenshots at exact Apple App Store dimensions (1242×2688, 1284×2778, and landscape variants) and download ready-to-submit PNGs.

Convert images to ASCII art in your browser — upload a file or paste a URL, with configurable width and character density.

Encode and decode base64 strings with live sync and shareable permalinks.

Generate HTTP Basic Authentication headers from a username and password — encoded in your browser.

Visualize AND, OR, XOR, NAND, NOR, and shift operations with binary and decimal output side by side.

Convert between byte units — B, KB, KiB, MB, MiB, GB, GiB, TB, TiB — with binary (1024) and decimal (1000) modes.

Convert between numeric and symbolic Unix file permission modes with a visual breakdown table.

Calculate subnet details from CIDR notation: network address, broadcast, mask, host range, and more.

Convert color values between HEX, RGB, RGBA, HSL, and OKLCH with live preview.

Generate a perceptually uniform 11-step color scale in OKLCH — ready for Tailwind CSS or any design system.

Compress PNG, JPEG, and WebP images server-side. Convert to WebP or AVIF for maximum file size reduction.

Parse cron expressions into plain English and preview the next 10 scheduled run times.

Parse, visualize, and audit a Content-Security-Policy — flag unsafe-inline, wildcards, missing directives, and clickjacking gaps. Paste a header or fetch one from any URL.

Convert between CSS units: px, rem, em, %, vh, vw, pt, cm, mm, in with adjustable context.

Convert timestamps and dates between many formats at once with live sync and shareable permalinks.

Generate MD5, SHA-1, SHA-256, SHA-384, and SHA-512 hashes from any text input.

Encode and decode HTML entities for safe display in web pages with multiple encoding modes.

Convert a JSON sample into TypeScript interface definitions instantly.

Convert between JSON and YAML formats with live bidirectional sync and shareable permalinks.

Compare two JSON structures and highlight added, removed, and changed keys recursively.

Decode JWT tokens and inspect header, payload claims, and expiry status.

Press any key to inspect its JavaScript event properties: key, code, keyCode, location, and modifier state.

Generate lorem ipsum placeholder text by words, sentences, or paragraphs with one click.

Convert Markdown to HTML with a live preview. Toggle between rendered output and raw HTML source.

Look up your current public IP address with geolocation, ASN, and network details.

Convert integers between binary, octal, decimal, and hex with live sync and shareable permalinks.

Generate Open Graph and Twitter Card meta tags with a live social preview.

Generate cryptographically secure passwords with configurable length, character sets, and count.

Placeholder images at any size — crop the photo library or generate a seeded SVG pattern, then preview the hotlinkable URL live.

Format and validate JSON with live pretty-printing and shareable permalinks.

Generate QR codes from any text or URL and download as SVG or PNG.

Test regular expressions against strings with live match results and shareable permalinks.

A scratchpad — type anything and bookmark it as a shareable permalink.

Format and prettify SQL queries with uppercase keywords and proper indentation. Supports PostgreSQL, MySQL, SQLite, and BigQuery.

Convert text between camelCase, PascalCase, snake_case, kebab-case, SCREAMING_SNAKE, Title Case, and more.

Convert SVG markup to React JSX — removes xmlns, converts hyphenated attributes to camelCase, and wraps inline styles as objects.

Compare two blocks of text and highlight additions and deletions line by line.

Analyze text statistics: character count, word count, reading time, and word frequency analysis.

Inspect each character's code point, UTF-8/UTF-16 encoding, category, script, and HTML entity.

Encode and decode URL strings with live sync and shareable permalinks.

Generate UUIDs of any version with one click and shareable permalinks.

Proxy iframes securely with full event handling and introspection for debugging.

Capture and inspect frame messages in real time.

Design and trigger postMessage actions with an interactive viewer and designer.

Capture and inspect incoming HTTP webhook requests in real time.

Generate RSA-OAEP key pairs, encrypt messages, and decrypt them in-browser using the Web Crypto API.

Serve a public GitHub Gist's raw content via a proxy URL, with live iframe preview.

Capture the current browser tab as a PNG and open it in a new tab.

Test and inspect HTML video element behavior — buffering, events, and playback state — with full telemetry.

Send a test push notification to a registered mobile device.

Test and inspect HTML audio element behavior — buffering, events, and playback state — with full telemetry.

Defer the page load event by a configurable number of milliseconds — a slow-loading target for testing iframe load handling.

An httpbin-compatible request & response service — inspect headers, force status codes, and test auth, redirects, cookies, and delays.

All 128 ASCII characters with decimal, hexadecimal, octal, and named descriptions.

All CSS selector types with descriptions, examples, and specificity values: basic, attribute, pseudo-class, pseudo-element, and combinators.

A, AAAA, CNAME, MX, TXT, NS, SOA, SRV, CAA, and DNSSEC records — what each does, when to use it, and example syntax.

Standard Unix/Linux process exit codes: 0 success, 1 general error, 126/127 shell errors, and 128+N signal offsets.

Request and response header fields: caching, authentication, CORS, security, content negotiation, and more.

Complete reference for HTTP response status codes: 1xx through 5xx, with descriptions, use cases, and caching behavior.

All icons available via @expo/vector-icons Ionicons — 422 base icons each with filled, outline, and sharp variants, plus 94 logo icons. Searchable by name, filterable by category.

Info.plist usage description keys for location, camera, microphone, contacts, health, Bluetooth, identity, and more.

System URL schemes for Phone, FaceTime, Messages, Mail, Maps, App Store, and Settings — with examples and notes.

Lesser-known and essential macOS keyboard shortcuts — Finder (⌘⇧. for hidden files), screenshots, Spotlight, windows, text editing, accessibility, power, and startup keys.

Example MP4 video files for testing HTML video behavior: a standard file and a fast-start variant with the moov atom at the front for immediate buffering.

Content-Type values for text, application, image, audio, video, font, and multipart formats with file extensions.

Well-known TCP and UDP port numbers grouped by category: web, remote access, database, mail, file transfer, network, and more.

Postgres operators for JSONB and array values: access (->, ->>, #>), containment (@>, <@), existence (?, ?|, ?&), modification (||, -, #-), and path queries (@?, @@).

Complete reference for psql backslash commands — informational \d* listings, formatting, I/O, conditionals, connection, and more.

Regular expression quick reference: anchors, character classes, quantifiers, groups, lookaheads, flags, and escape sequences.

IANA timezone names with live current time, UTC offsets, abbreviations, and major cities.

Default tmux prefix key bindings (C-b) for sessions, windows, panes, layouts, and copy mode, plus CLI subcommands with full syntax.

Named code point ranges from Basic Latin to Supplementary planes, with assigned character counts and sample glyphs.

Signal numbers, names, and default actions for POSIX signals — from SIGTERM and SIGKILL to SIGWINCH and SIGCHLD.