What is MIME type "image/svg"?

A MIME type is a string that tells browsers and other tools how to handle a particular kind of file.

The MIME type image/svg defines graphics through code rather than pixels.
It represents scalable vector graphics that can resize without losing quality.

Used in web design for crisp logos and icons
Ideal for responsive layouts that adjust across devices
Supports interactive and animated graphics in web applications

It handles files like SVG and compressed SVGZ.
These are text-based formats that browsers render directly and can be modified with CSS and JavaScript.
The format is standardized by the W3C and widely supported across modern software.
For more details, visit W3C SVG.

Associated file extensions

.svg, .svgz

Usage Examples

HTTP Header

When serving content with this MIME type, set the Content-Type header:


    Content-Type: image/svg

HTML

In HTML, you can specify the MIME type in various elements:


    <a href="file.dat" type="image/svg">Download file</a>

Server-side (Node.js)

Setting the Content-Type header in Node.js:


    const http = require('http');    
    
    http.createServer((req, res) => {    
      res.setHeader('Content-Type', 'image/svg');    
      res.end('Content here');    
    }).listen(3000);

Associated file extensions

.svg, .svgz

FAQs

What is the correct MIME type for SVG files?

The official IANA standard MIME type for SVG files is image/svg+xml. While you might occasionally see image/svg referenced in older documentation, modern web servers and browsers require the +xml suffix to parse the file correctly as an XML-based vector image.

How do I configure Apache to serve SVG files correctly?

To ensure Apache serves SVGs with the correct headers, add the following line to your .htaccess file or main configuration: AddType image/svg+xml .svg .svgz. Additionally, if you are serving compressed .svgz files, you must add AddEncoding gzip .svgz.

Why is my SVG file downloading instead of displaying in the browser?

This issue occurs when the web server sends the wrong Content-Type header, often defaulting to application/octet-stream. To fix this, update your server configuration to explicitly map the .svg extension to image/svg+xml.

Are there security risks associated with SVG files?

Yes, because SVGs are XML documents that can contain JavaScript, they are vulnerable to Cross-Site Scripting (XSS) attacks. You should never allow users to upload SVGs that are rendered directly without sanitizing the code first using a library like DOMPurify.

What is the difference between .svg and .svgz?

An .svg file is a standard text-based vector file, while .svgz is the GZIP-compressed version of that file. The MIME type remains image/svg+xml for both, but .svgz requires the server to send a Content-Encoding: gzip header for the browser to decompress it.

When should I use SVG over PNG or JPEG?

Use SVG for logos, icons, and illustrations that need to scale to different sizes without looking pixelated. For complex photographs with millions of colors, raster formats like image/jpeg or image/png are generally more efficient.

How do I add SVG support to Nginx?

Open your mime.types file (usually located in /etc/nginx/) and ensure the following line exists: image/svg+xml svg svgz;. If you modify this file, remember to reload Nginx using sudo service nginx reload for the changes to take effect.

General FAQ

What is a MIME type?

A MIME (Multipurpose Internet Mail Extensions) type is a standard that indicates the nature and format of a document, file, or assortment of bytes. MIME types are defined and standardized in IETF's RFC 6838.

MIME types are important because they help browsers and servers understand how to process a file. When a browser receives a file from a server, it uses the MIME type to determine how to display or handle the content, whether it's an image to display, a PDF to open in a viewer, or a video to play.

MIME types consist of a type and a subtype, separated by a slash (e.g., text/html, image/jpeg, application/pdf). Some MIME types also include optional parameters.

How do I find the MIME type for a file?

You can check the file extension or use a file identification tool such as file --mime-type on the command line. Many programming languages also provide libraries to detect MIME types.

Why are multiple MIME types listed for one extension?

Different applications and historical conventions may use alternative MIME identifiers for the same kind of file. Showing them all helps ensure compatibility across systems.