What Is SVG to Base64 Conversion?
SVG to Base64 conversion transforms SVG XML markup into a Base64-encoded data URI prefixed with data:image/svg+xml;base64,. The converter UTF-8 encodes the SVG string, then applies Base64 encoding to produce a text-safe output. This data URI can be used in CSS background-image properties, HTML <img> tags, and JSON payloads where direct SVG embedding is not possible.
Why Convert SVG to Base64?
Base64-encoded SVG can be embedded in CSS background-image declarations where inline SVG markup is not supported. It eliminates HTTP requests for small vector icons, allows SVG inclusion in JSON data structures, and enables single-file HTML documents with embedded vector graphics. Base64 also avoids URL-encoding complexities that arise when placing raw SVG in CSS url() values. For encoding raster images, use the Base64 image encoder.
How Does SVG to Base64 Encoding Work?
SVG is an XML-based text format. For file uploads, the FileReader API reads the SVG as a data URL. For pasted markup, the converter applies UTF-8 encoding via encodeURIComponent() and unescape(), then Base64 encodes the result with btoa(). The output includes the data:image/svg+xml;base64, prefix. All processing runs in your browser memory with no server communication. Learn the encoding fundamentals at What Is Base64.
Should You Use Base64 or Inline SVG?
The choice depends on where and how you use the SVG. The following table compares Base64 SVG, inline SVG, and external SVG files across key criteria.
| Criteria | Base64 SVG | Inline SVG | SVG File |
|---|---|---|---|
| CSS background-image | Yes | No | Yes (external URL) |
| DOM access / scripting | No | Yes | No (unless <object>) |
| Browser caching | No (inline) | No (inline) | Yes |
| File size overhead | +33% from Base64 | None | None |
| Editable after embedding | No | Yes | Yes (source file) |
Use Base64 SVG for CSS backgrounds and JSON embedding. Use inline SVG in HTML when you need DOM interaction or animation control. Use external SVG files for large graphics that benefit from browser caching. Compare binary vs text encoding at Base64 vs binary. Generate embed code at the Base64 embed generator.
What Are the Best Practices for SVG Base64 Encoding?
Remove unnecessary metadata, comments, and editor-specific attributes from SVG markup before encoding. Optimize with SVGO or a similar tool to reduce file size. Use Base64 SVG primarily for CSS background-image where inline SVG is not supported. For HTML embedding, prefer inline SVG for smaller output and DOM access. Consider URL-encoding (data:image/svg+xml, without Base64) as an alternative that produces smaller strings for simple SVGs. Embed CSS-ready code with the Base64 CSS tool. To decode SVG back from Base64, use the Base64 to SVG converter.
Frequently Asked Questions
Can I paste SVG code directly?
Yes, paste raw SVG markup into the text area and click "Encode SVG Markup." You can also upload an .svg file using the file input. Both methods produce the same Base64 data URI output.
Is Base64 the best way to embed SVG in CSS?
For background-image, yes. Inline SVG cannot be used in CSS background-image properties. Base64 encoding is the most reliable method for embedding SVG in stylesheets. For HTML, inline SVG is more flexible because it allows DOM access and CSS styling.
Does Base64 increase SVG file size?
Yes, approximately 33% larger. Since SVG is already a text-based format, the Base64 overhead is less justified than for binary formats like PNG or JPEG. URL-encoding (data:image/svg+xml,) is a smaller alternative for simple SVGs in CSS.
Can I edit Base64-encoded SVG?
Not directly. You must first decode the Base64 string back to SVG markup, make your edits, then re-encode the modified SVG. Use the Base64 to SVG converter to decode.
Is my SVG data kept private?
Yes, all processing is local in your browser. SVG data is encoded using JavaScript and never leaves your device. No data is transmitted to any server.