Image to Base64 Converter

What is Base64 image encoding?

Base64 is a way to encode binary data (like images) as plain text using only 64 characters: A-Z, a-z, 0-9, +, /. An image converted to Base64 becomes a long text string that starts with "data:image/png;base64," followed by the encoded data. You can paste this string directly into HTML (in the src attribute of an img tag), CSS (in a background-image property), or JSON.

When to use Base64 images

Base64 is useful for: email templates (some email clients block external images, but Base64 embedded images always load), small icons in CSS (avoids extra HTTP requests), offline HTML (the file is self-contained), single-file SVG (Base64 SVG can be embedded in other documents), and data URIs in web APIs. Don't use Base64 for large images — a 500KB JPEG becomes a 670KB Base64 string, and Base64 can't be cached as efficiently as separate image files.

Browser support and performance

All modern browsers support Base64 images in HTML and CSS. Performance trade-off: Base64 images load synchronously with the HTML, which can delay page rendering if the image is large. Best practice is to use Base64 for icons under 5KB (each), regular image files for anything larger. Some build tools (Webpack, Vite) can auto-encode small images as Base64 during optimization.