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ql-win/quicklook

📈 Trending★ 23,425C#Audience · vibe coderComplexity · 2/5ActiveLicenseSetup · easy

TLDR

Press spacebar in Windows File Explorer to instantly preview any file without opening it, images, videos, PDFs, code, and 100+ formats.

Mindmap

mindmap
  root((QuickLook))
    What it does
      Instant file preview
      Spacebar trigger
      No app launch
    Supported formats
      Images and video
      Documents
      Code and text
      Archives and 3D
    How to use
      Press space to preview
      Press space to close
      Works in File Explorer
    Benefits
      Save time browsing
      Check before opening
      Lightweight background app

Things people build with this

USE CASE 1

Quickly preview photos, videos, or documents in File Explorer without waiting for apps to load.

USE CASE 2

Browse code files with syntax highlighting to find the right script before opening it in an editor.

USE CASE 3

Check file contents in save/open dialogs to confirm you're selecting the right file.

USE CASE 4

Preview archives, 3D models, and fonts to decide if you need to extract or use them.

Tech stack

C#.NETWindows API

Getting it running

Difficulty · easy Time to first run · 5min
Use it freely, but any project you distribute that includes this code must also be GPL-licensed and open source.

In plain English

QuickLook is a Windows application that brings one of macOS's most loved features to Windows: press the spacebar on any file in File Explorer and instantly see a preview without opening the associated program. Press space again or click away and the preview disappears. On macOS this works natively for images, PDFs, videos, and more. Windows has never had this. Without QuickLook, previewing a file on Windows means double-clicking, waiting for an application to load, viewing the file, and then closing the application, several slow steps just to peek at something. QuickLook handles over 100 file types: images (JPEG, PNG, GIF, WebP, RAW), videos (MP4, MKV, AVI), documents (PDF, Word, Excel, PowerPoint), code files with syntax highlighting, Markdown, 3D models (OBJ, STL), archives (ZIP, RAR), fonts, audio files, and more. It also supports plugins to add even more formats. It integrates with File Explorer, Windows open/save dialogs, and some third-party file managers. You would use this if you frequently browse files on Windows and want a faster way to check what a file contains before deciding whether to open it fully. It installs as a background application and stays out of the way until you press space. It is written in C# and runs only on Windows.

Copy-paste prompts

Prompt 1
How do I install QuickLook on Windows and set it up to preview files in File Explorer?
Prompt 2
Show me how to create a custom plugin for QuickLook to preview a file format it doesn't support yet.
Prompt 3
What are the keyboard shortcuts in QuickLook and how do I configure them?
Prompt 4
How do I troubleshoot QuickLook if the spacebar preview isn't working in File Explorer?
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Generated 2026-05-18 · Model: sonnet-4-6 · Verify against the repo before relying on details.