A growing collection of free, browser-based utilities for developers and power users — PDF tools, encoding converters, code formatters, security generators. Everything runs client-side: no file uploads, no accounts, no tracking, no server.
Extract any page range or split every page into individual files. Download as a ZIP. 100% client-side.
Combine two PDFs. Append or insert at any page. Download instantly.
Resize every page to A4, A3, A5, Letter, Legal or custom. Fit / Fill / Stretch. Portrait or Landscape.
Rotate all pages or a custom range by 90°, 180°, or 270°. Nothing leaves your browser.
Stamp custom text on all pages. Pick colour, opacity, rotation, font size, centred or tiled. Live preview.
Render every page as a PNG (or JPEG) at 72, 144, or 300 DPI. White or transparent background. Download individually or as ZIP.
Format, validate, minify JSON in-browser. Syntax highlighting, clear error reporting, character/line stats.
Live testing with capture-group breakdown, flag toggles (g, i, m, s, u), and a built-in cheat sheet.
Encode special characters to HTML entities or decode them back. Live preview and searchable entity reference.
Convert Markdown to HTML with a live preview. Headers, tables, code blocks, lists, blockquotes, links, images.
Configurable length and char sets. Entropy display, ambiguous-char exclusion, visual strength meter.
Cryptographically secure SECRET_KEY values for Django settings. Configurable, with code snippets.
Decode header, payload, signature. Human-readable timestamps, expiry detection, syntax highlighting.
Encode/decode text or binary data. URL-safe mode, file input, entirely client-side.
Crop PNG, JPEG, WebP, GIF or BMP images. Drag the selection box to move it, grab any of eight handles to resize. Lossless PNG output.
Resize images to any pixel width or height. Aspect-lock, percentage presets (25–200%) and PNG/JPEG/WebP output with quality control.
Slide the quality, watch the savings. Re-encode JPEG or WebP entirely client-side with live before/after file-size comparison.
Stamp text or a logo on any image. Pick rotation, layout (centre or tiled), colour and opacity — live preview, lossless PNG output.
Combine one or more images into a single PDF. A4/Letter/A5/A3 page sizes, orientation, margin and image-fit controls.
Image → multi-resolution favicon.ico + 16/32/48/180/192/512 PNGs + site.webmanifest, packed as a ZIP with a paste-ready HTML snippet.
Generate UUID v4 (random) and v7 (time-ordered) in bulk. Format options: uppercase, no hyphens, braces. Copy or download as .txt.
Placeholder text by paragraphs, sentences, or words. Optional <p> tag wrapping and classic "Lorem ipsum" opening. Copy or download.
Turn any URL or text into a QR code. Custom colours, size, margin and error correction. Download as PNG or SVG, or copy straight to clipboard.
Decode a QR from an image upload or a live webcam scan. Auto-parses URLs, WiFi, vCard, MeCard, SMS and email payloads. Copy or open straight from the result.
SSID, password, WPA / WEP / open, hidden-network toggle — encoded as the standard WIFI: payload that iOS and Android join in one tap.
Name, organisation, title, phone, email, website and address → vCard 3.0 or MeCard QR. Built for business cards and email signatures.
Live HEX ↔ RGB ↔ HSL ↔ OKLCH converter with CSS Color 4 support. Extract dominant-colour palettes from any image and export as CSS custom properties.
I add new client-side utilities here regularly. If there's something you'd use, drop me a line — most of these started as someone else's request.
$ ./suggest-a-tool →