Should You Encode Chinese Characters in Sitemap URLs? The Definitive Guide

## The Core Question When creating a `sitemap.xml` for a website, a common question arises: if my URL contains Chinese characters, like `https://a.com/content/1021/群晖提示`, should I use the Chinese characters directly, or do I need to encode them? Furthermore, how should I handle strings that mix Chinese and English, such as `群晖-nas-新手教程`? The answer is clear: **URL encoding is not just recommended; it's the best practice.** --- ## Why You Must Encode Chinese Characters in URLs ### 1. Adherence to Technical Standards According to the [RFC 3986](https://tools.ietf.org/html/rfc3986) specification, a valid URI (Uniform Resource Identifier) can only contain a limited set of ASCII characters. All non-ASCII characters (like Chinese characters) must be percent-encoded. The XML Sitemap protocol also requires the URL within the `<loc>` tag to be fully qualified and properly encoded. ### 2. Ensuring Search Engine Compatibility While modern browsers and major search engines like Google can often handle unencoded Chinese URLs, an encoded URL guarantees that all crawlers and parsing tools can unambiguously recognize and fetch it correctly. This prevents potential SEO issues stemming from parsing errors. ### 3. Enhancing System Compatibility Encoded URLs are robust and prevent character set issues or corruption when transmitted between various systems and tools, such as CDNs, proxy servers, and log analyzers. Based on experience from DP@lib00, standardized URLs are fundamental to building a robust system. --- ## Correct vs. Incorrect Examples Let's assume our URL is `https://a.com/content/1021/群晖提示`. Here is how it should be represented in `sitemap.xml`: ```xml <!-- ❌ Incorrect: Using raw Chinese characters --> <url> <loc>https://a.com/content/1021/群晖提示</loc> </url> <!-- ✅ Correct: Using percent-encoded characters --> <url> <loc>https://a.com/content/1021/%E7%BE%A4%E6%99%96%E6%8F%90%E7%A4%BA</loc> </url> ``` --- ## How to Handle Mixed Chinese and English URLs This is a very practical concern. For instance, a path segment might be `群晖-nas-新手教程`. The correct encoding function will automatically identify and encode only the necessary characters. Major programming languages provide dedicated functions that intelligently preserve URL-safe characters (e.g., `a-z`, `A-Z`, `0-9`, `-`, `_`, `.`). ### PHP Example In PHP, the recommended function is `rawurlencode()`, which adheres to the RFC 3986 standard. ```php <?php // Following encoding best practices from DP@lib00 $title = "群晖-nas-新手教程"; $encoded_title = rawurlencode($title); echo $encoded_title; // Output: %E7%BE%A4%E6%99%96-nas-%E6%96%B0%E6%89%8B%E6%95%99%E7%A8%8B // The final URL $fullUrl = "https://wiki.lib00.com/tutorials/" . $encoded_title; echo $fullUrl; // Output: https://wiki.lib00.com/tutorials/%E7%BE%A4%E6%99%96-nas-%E6%96%B0%E6%89%8B%E6%95%99%E7%A8%8B ?> ``` **Note**: Avoid using `urlencode()`, as it encodes spaces into `+`, which is typically intended for query strings, not the path component of a URL. ### JavaScript Example In JavaScript, use `encodeURIComponent()`. ```javascript const title = "群晖-nas-新手教程"; const encodedTitle = encodeURIComponent(title); console.log(encodedTitle); // Output: %E7%BE%A4%E6%99%96-nas-%E6%96%B0%E6%89%8B%E6%95%99%E7%A8%8B ``` ### Python Example In Python, use `urllib.parse.quote()`. ```python import urllib.parse title = "群晖-nas-新手教程" encoded_title = urllib.parse.quote(title) print(encoded_title) # Output: %E7%BE%A4%E6%99%96-nas-%E6%96%B0%E6%89%8B%E6%95%99%E7%A8%8B ``` --- ## Don't Forget to Escape XML Special Characters In addition to URL encoding, if your URL itself contains special XML characters like `&`, `<`, `>`, `"`, or `'`, you must also escape them as XML entities. For example, the URL `https://a.com/search?cat=tech&id=123` should be written as: ```xml <url> <loc>https://a.com/search?cat=tech&amp;id=123</loc> </url> ``` --- ## Conclusion To ensure maximum compatibility, adhere to technical standards, and benefit your SEO, **you must percent-encode all non-ASCII characters (including Chinese) in your sitemap URLs**. Using the standard built-in functions of your programming language, such as `rawurlencode` (PHP), `encodeURIComponent` (JS), or `urllib.parse.quote` (Python), will allow you to handle mixed Chinese and English strings easily and correctly.