QuickestLook

From the App Store Source

QuickestLook makes Quick Look beautiful. Press space on any file in Finder and see a preview that's actually useful. Source code with proper syntax highlighting. JSON as a collapsible tree. CSV as a real table. Markdown rendered the way you'd read it in a polished documentation site. Logs with colored levels and timestamps. Archives with their contents browsable. Dozens of formats, all designed to look like part of macOS — only better. PRIVACY FIRST QuickestLook never sends your files anywhere. Everything is rendered locally on your Mac. No analytics, no telemetry, no tracking. Even better: QuickestLook automatically masks values that look like secrets — API keys, tokens, passwords — when previewing config files. Quick Look an .env or .xcconfig file in front of someone and your credentials stay hidden. The detection runs locally; nothing leaves your Mac. WHAT GETS A BEAUTIFUL PREVIEW Source code: Swift, Python, Rust, Go, TypeScript, JavaScript, Ruby, Kotlin, Dart, GraphQL, Vue, Svelte, SCSS, Sass, Less, and more. Apple ecosystem: .plist, .entitlements, .xcconfig, .strings, .xcstrings rendered as readable key-value trees. Data and config: JSON, JSONL, YAML, TOML, INI, .env, .gitignore family, lock files for major package managers. Notebooks: .ipynb files with markdown cells, code highlighting, and embedded image outputs. Tabular: CSV, TSV with proper tables, sticky headers, zebra striping. Logs: timestamps, colored severity levels, stack-trace formatting. Archives: .zip contents browsable as a tree. Web: HTML, XML, SVG. Subtitles: .srt, .vtt, .ttml as timestamp/text timelines. Disk images: .dmg metadata. And more. DESIGNED FOR macOS 26 Two themes built in: Calm (subtle, native macOS feel) and Vivid (gradients, glows, accent bars). Pick what suits you, or write your own custom CSS for full control. CONFIGURATION Per-renderer enable/disable. Font size and family. File-size caps. Theme selection. Reveal-secrets toggle for when you actually need to see them. FREE TO USE QuickestLook is free. If it saves you time and you'd like to support development, optional supporter purchases are available inside the app. They unlock nothing — they're a thank-you. The app stays fully featured for everyone. LIMITATIONS WORTH KNOWING macOS routes each file type to a single Quick Look extension. If you have another app installed that claims a file type QuickestLook also supports, that other app's preview shows instead. The fix takes ten seconds: right-click the file → Get Info → "Open with: QuickestLook" → Change All. Details on the support page.

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