What is a Base64 image string used for?
Base64 encodes binary image data as text, so it can be embedded directly inside HTML, CSS, or JSON without a separate file request — common for icons, small images, and email templates.
Does converting to Base64 increase file size?
Yes, Base64 encoding adds roughly 33% overhead compared to the original binary file size, since it represents binary data using only text-safe characters.
Can I decode a Base64 string back to an image?
Yes. Switch to the Base64 → Image tab, paste the string (with or without the data:image/...;base64, prefix), and click Decode to Image, then download it.
What output formats does the copy button support?
You can copy the raw Base64 string, a ready-to-use CSS background-image: url() rule, or a complete HTML <img src="..."> tag.
Is my image uploaded to a server?
No. Encoding and decoding both happen entirely in your browser using the FileReader API. Your image and the resulting Base64 string never leave your device.