Utilities AI Apps

Free passport, visa & ID photo maker. Crop to official size with head guides, then download a print-ready 4x6/A4 sheet for CVS, Walgreens, or any pharmacy kiosk. Runs fully in your browser - no upload, no watermark.

A private file manager for your personal cloud storage — sign in with your SkillSafe account to upload files and folders, organize, preview, star, share links, and restore from trash.

Show your public IP, network edge details, and full browser & device information. All client-side; nothing stored.

See every invisible character in your text - zero-width spaces, directional overrides, tag characters, private-use codepoints, homoglyph spaces - each named, counted and located, then removed exactly, without breaking the joiners that hold emoji, Persian, Khmer, Hangul and regional flags together. Adds a zero-model style score for AI-like cadence and an optional model lane that either explains the findings or rewrites only the highest-signal paragraphs, with a word-level before-and-after diff. The scan, the reveal view, the style score and the clean all run free in your browser with no account. Method derived from github.com/guillaumemeyer/watermarks-remover (MIT, Guillaume Meyer) - this app is an independent re-implementation of that project's text layers, not a port of its code.

Translate text to International Morse Code and back. Play it as sound, flash it as a fullscreen light, export a flash-and-beep video for embedding, or decode Morse live from your microphone or camera — free, entirely in your browser.

Convert Word, Excel, PowerPoint, OpenDocument, EPUB, RTF, HTML, CSV and text-layer PDFs to clean GitHub-Flavored Markdown, entirely in the browser, with an optional metered AI pass that repairs heading hierarchy, undeclared PDF tables, merged headers, reading order and OCR noise, then reconciles its output against the parser's measured facts. Modelled on anydoc, the open-source (MIT) document parser by Firecrawl (github.com/firecrawl/anydoc); reimplemented in JavaScript for this runtime. Not affiliated with Firecrawl.

Draw causal-loop models, connect positive and negative relationships, and run animated feedback simulations entirely in your browser. Source: https://github.com/ncase/loopy

Free, private static QR codes with rich content types, custom styling, logos, and print-ready exports.

Paste a CSV or TSV export and get a data profile with judgement: the grain and whether the key actually holds, quality issues ranked by severity with the offending values quoted, the dimensions and metrics worth using, patterns to check, and 3-5 specific analyses to run first. The mechanical profiler runs free in your browser.

A clean, keyboard-friendly calculator.

Turn any web page into an importable Obsidian Web Clipper template. The free half is a real engine: paste the page's HTML and the browser extracts every meta tag, schema.org JSON-LD path and live CSS selector, generates a grounded skeleton template, validates any template against the Clipper import schema AND against the page, and previews the exact note it would clip. The AI pass shapes the template around your intent - and the same validator re-checks every selector, meta key and schema path it used, in public. A derived work of @sickn33/obsidian-clipper-template-creator (sickn33/antigravity-awesome-skills). Not affiliated with Obsidian.

A big-display countdown for running talks: start/pause/resume/reset plus a configurable warning threshold so the speaker sees their last N seconds on screen rather than a hand waving at the back. The whole setup encodes in the URL fragment (#300 for five minutes, #30,15 for thirty seconds warning at fifteen), so each talk format is a bookmarkable link. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (lightning-timer.html, Apache-2.0).

Pick two timezones and read the overlap off an hour-by-hour table showing the same instant in UTC and both local zones. Zones come from the browser's full IANA list and formatting goes through Intl.DateTimeFormat, so daylight saving is handled for the actual dates shown. The pairing is encoded in the URL, so the link reproduces it. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (timezones.html, Apache-2.0).

Arrange photos into a printable grid - portrait or landscape, photos per row, rows per page, fit or fill - and print at actual size with a preview that matches the paper. The print stylesheet hides the controls automatically. Photos never leave the browser. Imported Claude artifact. Source: https://github.com/simonw/tools (image-print.html, Apache-2.0).

Compare two JSON documents structurally - keys added, removed, changed - rather than as text, so reformatting and key reordering do not drown the real differences. Includes swap, clear and five worked examples. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (json-diff.html, Apache-2.0).

Drop an animated GIF and extract every frame with its real metadata - delay, disposal method, dimensions, offsets - rendered one by one. For pulling a still out of an animation, or working out what timings a GIF actually contains when it plays wrong somewhere. Decoded in your browser with no third-party CDN code; nothing is uploaded. Imported Claude artifact. Source: https://github.com/simonw/tools (gif-dissector.html, Apache-2.0).

Paste text and get words, characters and an estimated reading time at 230 words per minute, updating as you type. For sizing up an article before you commit to it, or working out what a 'x minute read' badge should honestly say. A rough guide - dense or technical writing reads slower than the flat assumption. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (reading-time.html, Apache-2.0).

Enter percentages, tick the ones to exclude, and see the rest renormalised to sum to 100 - with the active total shown as you go. For the everyday case of reporting a split among respondents who actually picked a side, without leaving a chart whose bars add to 91%. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (percentage-recalculator.html, Apache-2.0).

Press any keys and see what the browser actually reports: the key value (layout-dependent) alongside the physical code (not), for as many keys as you hold at once. The distinction is what decides whether a shortcut survives on someone else's keyboard layout. Modifier and navigation keys render as proper glyphs. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (keyboard-debug.html, Apache-2.0).

A multi-section writing pad where every section carries its own live word and character count - for when you are writing to a budget spread across parts rather than one total. Drafts save to your browser's local storage on a debounce, so a reload does not lose them. Nothing leaves the browser. Imported Claude artifact. Source: https://github.com/simonw/tools (word-counter.html, Apache-2.0).

Paste an epoch timestamp from a log, JWT or API response and read it as a full date - weekday, date, seconds, timezone - in both UTC and your local timezone, live as you type. Detects seconds versus milliseconds automatically from the digit count. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (unix-timestamp.html, Apache-2.0).

Paste a Pipfile.lock and get its pinned dependencies back as Pipfile entries and as requirements.txt lines, each with a copy button. Reads both default and develop sections, and skips entries with no pinned version rather than emitting broken pins. Handy for getting a requirements.txt out of a Pipenv project without installing Pipenv. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (pipfile.html, Apache-2.0).

Drop a JPEG and read its EXIF/TIFF orientation tag - the flag that decides whether a photo displays upright or sideways - with the raw value, its meaning, and debug detail like EXIF offset and file size. For settling which side of an upload pipeline is ignoring the tag. Parsed locally with DataView; the file is never uploaded. Imported Claude artifact. Source: https://github.com/simonw/tools (tiff-orientation.html, Apache-2.0).

Paste a bare millisecond duration from a log or benchmark and read it back as seconds, minutes, hours, days and weeks, plus a clock-style h:mm:ss.ms breakdown. Accepts numbers as you copy them - commas and underscores are stripped - and rejects non-numeric input rather than showing NaN. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (milliseconds.html, Apache-2.0).

Enter a file size (KB/MB/GB/TB) and a speed (MB/s, KB/s or Mbps) and see the transfer time as you type. Handles the bytes-versus-bits conversion that makes a 100 Mbps line move ~12.5 MB/s, not 100 - the usual source of a wildly optimistic estimate. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (transfer-time.html, Apache-2.0).

Convert text to and from HTML entities, live as you type. Escape mode handles the five characters that matter; unescape mode decodes named, numeric and hex references, which is what machine-generated HTML actually contains. Output is written with textContent, so your input is never rendered. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (escape-entities.html, Apache-2.0).

Paste text and see every smart quote, smart apostrophe, em dash and non-breaking space marked in place, with live counts per category. These are the characters that look fine in a document and then break a grep, a code block, or a diff. Covers the full U+2018-U+201F range, not just the common pair. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (curly-emdash.html, Apache-2.0).

Paste XML and get parse errors pinned to line numbers, highlighted in a numbered listing of your source. Checks well-formedness - unclosed tags, bad nesting, stray ampersands - not schema conformance. Uses the browser's own DOMParser, so the verdict matches your browser's. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (xml-validator.html, Apache-2.0).

Paste raw RTF markup - the {\rtf1\ansi... source itself - and get HTML with text colour, background colour and bold runs preserved as inline styles. The counterpart to a clipboard converter: for when you have RTF as text out of a file, an email source or a database column. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (rtf-to-html.html, Apache-2.0).

Choose a local folder and explore it in the browser: file tree, file and folder counts, total size, filter by type, a type-distribution chart, and click-to-preview for individual files. Built on <input webkitdirectory>; the browser hands over only what you select and nothing leaves the page. Imported Claude artifact. Source: https://github.com/simonw/tools (webkitdirectory.html, Apache-2.0).

Load a video, drag a crop box over the part you want to keep, and get the exact ffmpeg command - correct crop=w:h:x:y for the video's real pixel dimensions, plus an iPhone-compatible variant. The video loads locally as a blob for preview only; nothing is uploaded and no encoding happens in the browser. Imported Claude artifact. Source: https://github.com/simonw/tools (ffmpeg-crop.html, Apache-2.0).

Paste anything and see every MIME flavour the clipboard is really carrying - text/plain, text/html, text/rtf, image/png, vendor-specific types - with the raw payload behind each. Useful when a paste mysteriously loses formatting, or when writing paste-handling code. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (clipboard-viewer.html, Apache-2.0).

A Pomodoro timer that records what you worked on: pick 5-60 minutes, name the session goal, and every completed session lands in a persistent log with start/end times, duration and pause count. The countdown is wall-clock based, so backgrounding the tab does not make it drift. Stored locally in your browser; nothing is uploaded. Imported Claude artifact. Source: https://github.com/simonw/tools (pomodoro.html, Apache-2.0).

Count the span between two dates - all days, business days only, or weekends only - with the breakdown and a visual timeline of the range. Useful for deadlines quoted in working days, notice periods and billing windows. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (date-calculator.html, Apache-2.0).

Type text, pick from the voices installed on your own machine, and hear it spoken - with rate, pitch and volume sliders and a stop control. Uses the browser's built-in speechSynthesis API, so audio is generated on your device and nothing is uploaded. Imported Claude artifact. Source: https://github.com/simonw/tools (speech-synthesis.html, Apache-2.0).

Pretty-print JSON that a normal formatter rejects - truncated mid-string, missing closing braces, or still streaming - with live updates as you type, a validity indicator and input/output character counts. Handy for half-arrived payloads and streamed structured output. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (incomplete-json-printer.html, Apache-2.0).

Paste a note straight out of Apple Notes and get clean Markdown and HTML back, with hyperlinks preserved - the tool reads the RTF flavour of the clipboard rather than the flattened plain text. Runs entirely in your browser. Imported Claude artifact. Source: https://github.com/simonw/tools (notes-to-markdown.html, Apache-2.0).

Build a JSON Schema visually: add typed properties and nested objects, give the schema a title and description, and copy the generated JSON. Handy for tool/function-calling definitions and structured-output contracts. State lives in the URL so the link restores your work. Runs fully client-side. Imported Claude artifact. Source: https://github.com/simonw/tools (json-schema-builder.html, Apache-2.0).

Encrypt a message with a passphrase and share it as a link - the recipient opens the link, enters the passphrase, and reads the message. Uses browser WebCrypto (AES-GCM 256 with a PBKDF2-derived key, 100,000 iterations, random salt); nothing is uploaded. Imported Claude artifact. Source: https://github.com/simonw/tools (encrypt.html, Apache-2.0).

Open an image, click the colours you want removed, tune a tolerance slider to catch near-matching shades, and download a transparent PNG. Works with PNG, JPEG, GIF and WebP; drag, paste or pick a file. Fully offline in your browser - the image is never uploaded. Imported Claude artifact. Source: https://github.com/simonw/tools (transparent-png.html, Apache-2.0).

Draw pixel-perfect 24x24 icons with transparent backgrounds: click-drag to paint, erase, pick colours, or seed the grid from any emoji or character, then download a PNG. Your design is encoded in the URL, so the link restores your work. Imported Claude artifact, runs fully client-side. Source: https://github.com/simonw/tools (icon-editor.html, Apache-2.0).

Resize, crop and re-encode images entirely in your browser, then compare quality settings and file sizes side by side. Nothing is uploaded — the image never leaves the page. Imported Claude artifact. Source: https://github.com/simonw/tools (image-resize-quality.html, Apache-2.0).