# HTML Minifier

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[![License: MIT](https://img.shields.io/badge/License-MIT-blue.svg)](LICENSE.md)
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A fast and efficient command-line tool to minify your HTML, Razor views, and Web Forms views. Reduce file sizes, improve load times, and deliver a better user experience by removing unnecessary whitespace and comments from your HTML files.

## ✨ Features

- 🚀 **Fast Processing** - Minifies files and entire directory trees quickly with parallel processing
- ⚡ **Parallel Processing** - Utilizes all CPU cores for maximum performance (4-8x faster on multi-core systems)
- 📊 **Beautiful Reporting** - Comprehensive statistics with progress tracking and professional visual presentation
- 📁 **Flexible Input** - Process individual files, specific folders, or entire directory structures
- ⚙️ **Configurable** - Control line length and selectively disable minification features
- 🔧 **Framework Support** - Special handling for Knockout.js, Angular, and other comment-dependent frameworks
- 🎯 **Targeted Minification** - Choose what to minify: HTML comments, JavaScript comments, or Knockout comments
- 🛡️ **Safe Minification** - Preserves content inside `<pre>`, `<textarea>`, and `<code>` tags, and normalises attribute whitespace
- 🔄 **CI/CD Ready** - Easy integration with MSBuild and build pipelines

## 📊 Beautiful Reporting

Every run finishes with a clear, colour-coded summary - per-file savings plus overall compression, throughput, and elapsed time:

<img src="docs/images/reporting.png" alt="HTML Minifier console reporting output showing per-file savings and a minification summary" width="400">

## 📦 Installation

See [INSTALL.md](INSTALL.md) for release downloads, prerequisites, installation,
and instructions for obtaining and building the source.

## 🚀 Quick Start

Transform verbose HTML into compact, optimized code:

### Before:

```html
<h2>
    Admin Menu</h2>
<ul>
    <li>@Html.ActionLink("Edit blog entries", "List", "Admin")</li>
    <li>@Html.ActionLink("View Comments", "CommentList", "Admin")</li>
    <li>@Html.ActionLink("Clear Cache", "ClearCache", "Admin")</li>
</ul>
```

### After:

```html
<h2> Admin Menu</h2><ul><li>@Html.ActionLink("Edit blog entries", "List", "Admin")</li><li>@Html.ActionLink("View Comments", "CommentList", "Admin")</li><li>@Html.ActionLink("Clear Cache", "ClearCache", "Admin")</li></ul>
```

## 📖 Usage

### Getting Help

View all available options:

```bash
HtmlMinifier.exe --help
```

Check the version:

```bash
HtmlMinifier.exe --version
```

### Basic Usage

Minify all HTML files in a folder (including subfolders):

```bash
HtmlMinifier.exe "C:\Folder"
```

### Advanced Options

#### Limit Line Length

Restrict the maximum number of characters per line:

```bash
HtmlMinifier.exe "C:\Folder" "60000"
```

#### Preserve Comments

For frameworks that rely on HTML comments (Angular, Knockout, etc.), preserve them:

```bash
HtmlMinifier.exe "C:\Folder" ignorehtmlcomments
```

#### Preserve JavaScript Comments

Keep JavaScript comments in your code:

```bash
HtmlMinifier.exe "C:\Folder" ignorejscomments
```

#### Preserve Knockout Comments

Specifically preserve [Knockout.js](http://knockoutjs.com/) comments:

```bash
HtmlMinifier.exe "C:\Folder" ignoreknockoutcomments
```

### Multiple Targets

#### Minify Multiple Folders

```bash
HtmlMinifier.exe "C:\Folder\fld1" "C:\Folder\fld2"
```

#### Minify Specific Files

```bash
HtmlMinifier.exe "C:\Folder\file1.html" "C:\Folder\file2.html"
```

## 🔨 Build Integration

Integrate HTML Minifier into your build process for automatic minification during deployment. Check out this [detailed guide on using HTML Minifier with MSBuild](https://deanhume.com/a-simple-html-minifier-for-asp-net/).

## 🛡️ What Gets Preserved

The following content is never altered by minification:

- **`<pre>`, `<textarea>`, `<code>` tags** — internal whitespace is kept exactly as-is
- **IE conditional comments** — `<!--[if IE]>`, `<!--[if !IE]><!-->`, and `<!--<![endif]-->` patterns are all preserved
- **`#include` virtual comments** — ASP.NET server-side includes are left intact
- **Knockout comments** — `<!-- ko -->` / `<!-- /ko -->` are preserved when `ignoreknockoutcomments` is set
- **Razor declarations** — `@model`, `@using`, `@inherits` are kept and correctly re-arranged
- **Attribute values** — content inside quotes is preserved; leading/trailing whitespace is normalised

## 🤝 Contributing

Contributions are welcome. Read [CONTRIBUTING.md](CONTRIBUTING.md) for the
development setup, coding standards, acceptance requirements, and pull request
process.

To report a bug or propose an enhancement, follow [SUPPORT.md](SUPPORT.md).

## 📝 Requirements

- .NET Framework (Windows)
- Supports HTML, Razor (.cshtml), and Web Forms (.aspx) files

## 📄 License

Copyright (C) Dean Hume 2013 - 2026

Released under the [MIT License](LICENSE.md)

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**Made with ❤️ by [Dean Hume](https://deanhume.com)**