Image to Base64 Converter
Convert images to Base64 encoded strings instantly. Output as Data URI, CSS background, HTML img tag, or raw Base64. Free, client-side tool.
How to Use
- Drop an image onto the upload area or click to browse for a file.
- View the image preview, file info, and dimensions.
- Choose an output format: Data URI, Raw Base64, CSS, HTML, or Markdown.
- Click Copy to copy the result to your clipboard.
What Is a Data URI?
A Data URI (Uniform Resource Identifier) embeds file data directly in a URL string using the format data:[MIME type];base64,[data]. For images, this means you can include the entire image content in an HTML src attribute or CSS url() value without referencing an external file. The browser decodes the Base64 data and renders the image inline.
When to Use Base64 Images
- Small icons and UI elements — Inline small images under 10KB to eliminate HTTP requests
- Email templates — Many email clients block external images; inline Base64 images display reliably
- Single-file HTML — Create self-contained HTML documents with embedded images
- CSS sprites replacement — Embed small icons directly in CSS files
- API responses — Return small thumbnails or avatars as Base64 strings in JSON
When NOT to Use Base64 Images
Avoid Base64 for images larger than 10KB. The 33% size increase means a 100KB image becomes 133KB of text, and the Base64 string cannot be cached separately from the HTML/CSS file. Large Base64 strings also block HTML parsing and increase document size. Use regular <img> tags with properly optimized image files for anything beyond small icons.
Related Tools
Encode and decode text with Base64 Encoder. Generate Data URIs from text with the URL Encoder. Create QR codes from data URIs with the QR Code Generator. Format HTML with embedded images using the HTML Beautifier. Convert hex color codes with the Number Base Converter. Escape strings for embedding in code with the String Escape Tool.
Frequently Asked Questions
- What is Image to Base64?
- Image to Base64 converts a binary image file into a Base64-encoded text string. This string can be embedded directly into HTML, CSS, or JavaScript without needing a separate image file, reducing HTTP requests.
- When should I use Base64 images?
- Base64 images are best for small icons, logos, and UI elements under 10KB. They eliminate an HTTP request per image, improving load times for small assets. For images larger than 10KB, use regular image files instead — Base64 encoding increases the data size by about 33%.
- Does Base64 encoding increase file size?
- Yes. Base64 encoding increases the data size by approximately 33% because it represents 3 bytes of binary data using 4 ASCII characters. A 10KB image becomes roughly 13.3KB as Base64 text.
- Is my image uploaded to a server?
- No. The image is processed entirely in your browser using the FileReader API. Your image never leaves your device.
- What image formats are supported?
- All browser-supported image formats work: PNG, JPEG, GIF, SVG, WebP, ICO, BMP, and AVIF. The MIME type is automatically detected and included in the Data URI.
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