Paste a Base64 string or data URI to instantly preview the decoded image. Auto-detects image format (PNG, JPG, WebP, GIF, SVG), shows file size, and lets you download the image or copy the clean base64 string. Drag-and-drop supported.
Paste a raw Base64 string or a full data URI (data:image/png;base64,...) into the input area. You can also drag and drop an image file directly onto the input.
The image is decoded and displayed as a live preview instantly. The detected MIME type, dimensions, and file size are shown below the preview.
Click Download Image to save the decoded image to your device. Click Copy Base64 to copy the clean base64 string without the data URI prefix.
Base64 encodes binary image data as a printable ASCII string so images can be embedded directly in HTML, CSS, or JSON without a separate file request. It increases file size by ~33% but eliminates HTTP requests for small images like icons and inline SVGs.
A data URI is a full Base64 reference in the format: data:[mime-type];base64,[encoded-data]. Example: data:image/png;base64,iVBORw0KGgo… This can be used directly as an img src or CSS background-image URL.
Best for small images under 5KB (icons, logos, inline SVGs) where eliminating an HTTP request outweighs the size increase. Avoid for large images as the ~33% size overhead and inability to be cached separately makes them inefficient.
The tool auto-detects PNG, JPG/JPEG, GIF, WebP, SVG, BMP, and AVIF from the Base64 header bytes (magic numbers). If the format cannot be detected, it defaults to PNG for decoding.
Yes — all decoding happens entirely in your browser using JavaScript. No data is sent to any server. Your Base64 strings and decoded images never leave your device.
Browser memory limits apply. In practice, Base64 strings up to about 10MB (representing ~7.5MB images) work in most modern browsers. For larger images, use a server-side tool.
