File to Base64

File to Base64 | Base64 Converter Online

Encode files to Base64 online. Convert any file to Base64 content for embedding in HTML, JSON, or XML. Free file to Base64 converter.

Drag & drop a file here, or click to browse

Maximum file size: 10.00 MB

Use Cases

  • • Embed images directly in HTML/CSS
  • • Send binary data through JSON APIs
  • • Store files in databases as text
  • • Email attachments (MIME encoding)

Features

  • Encode any file type to Base64
  • Drag-and-drop file upload
  • Live file size and Base64 size preview
  • Support for images, PDFs, ZIP files, and more
  • Client-side encoding (files never leave your browser)
  • Copy Base64 output or download as .txt file

Common Use Cases

  • Embed images in HTML img src attributes
  • Send binary files through JSON APIs
  • Include logos and assets in email templates
  • Convert fonts for CSS @font-face embedding
  • Create data URIs for inline CSS backgrounds

File to Base64 Conversion

File to Base64 encoding converts any file's binary content into a text-safe Base64 string that can be embedded directly in HTML, CSS, JSON, or transmitted via APIs.

Common use cases:

  • Data URIs - data:image/png;base64,iVBORw0KG...
  • HTML embedding - <img src="data:image/png;base64,..."/>
  • CSS backgrounds - background-image: url(data:...)
  • API payloads - Send files in JSON without multipart/form-data

File size considerations: Base64 encoding increases file size by ~33%. A 100KB image becomes ~133KB when encoded. For large files, direct file uploads are more efficient.

Best practices: Use file-to-Base64 for small assets (<50KB) that need to be embedded. For larger files, use standard file uploads or CDN hosting.

Examples

Valid - Small image encoded to data URI
File: logo.png (2.3 KB)
Base64: iVBORw0KGgoAAAANSUhEUgAAAAUA...
Data URI: data:image/png;base64,iVBORw0KG...
Valid - PDF file for API transmission
File: document.pdf (15 KB)
Base64: JVBERi0xLjQKJeLjz9MKMSAwIG9ia...
Use in JSON: {"file": "JVBERi0xLjQKJe..."}
Invalid - Large file - not recommended for Base64
File: video.mp4 (50 MB)
// Too large! Base64 would be ~67 MB
// Use direct upload instead

Frequently Asked Questions

What file types can I convert to Base64?

You can convert any file type to Base64—images (PNG, JPG, GIF, SVG), documents (PDF, DOC), archives (ZIP, RAR), fonts (TTF, W OFF), videos, executables, and more. Base64 treats all files as binary data regardless of format.

How do I use Base64-encoded images in HTML?

Use a data URL in the src attribute:

<img src="data:image/png;base64,iVBORw0KGgo..." alt="Logo">

The format is: data:[MIME-type];base64,[BASE64-data]

What's the maximum file size I should encode to Base64?

For browser performance, keep Base64-encoded files under 50-100KB. Larger files cause longer encoding times, increased memory usage, and bloated HTML/CSS. For files >100KB, use direct uploads or CDN hosting instead.

Are my files uploaded to a server?

No. All file encoding happens client-side in your browser using JavaScript. Your files never leave your computer, ensuring complete privacy and security. The tool uses the browser's FileReader API to process files locally.

Can I decode Base64 back to the original file?

Yes! Use a Base64 decoder to convert the Base64 string back to binary data, then save it with the correct file extension. Our Encode/Decode tool supports this, or you can use the browser's atob() function with Blob APIs.