Base64 Image Viewer

Base64 is a binary-to-text encoding scheme that represents binary data as ASCII characters. When applied to images, it converts the raw image bytes into a text string that can be embedded directly in HTML, CSS, JSON, or any text-based format. This is commonly used for embedding small images inline without requiring a separate HTTP request.

A base64-encoded image can appear in two forms: as a raw base64 string (just the encoded characters) or as a data URL (with a prefix like "data:image/png;base64,"). Data URLs are used directly in HTML img tags, CSS background-image properties, and JavaScript. This tool accepts both formats and auto-detects the image type from the binary data.

The auto-detection feature reads the first few bytes of the decoded image (called "magic bytes" or file signatures) to identify the format. PNG files start with a specific 8-byte signature, JPEG files start with FF D8 FF, GIF files start with "GIF89a" or "GIF87a", and so on. This means you can paste a raw base64 string without any prefix and the tool will still display it correctly.

Common use cases for base64 images include: embedding icons in CSS to reduce HTTP requests, storing thumbnails in JSON API responses, including images in email HTML, embedding assets in single-file HTML exports, and passing image data through text-only channels. The trade-off is that base64 encoding increases the data size by roughly 33%.

This tool runs entirely in your browser. Your base64 data is never uploaded to any server — the image is decoded and rendered locally using a standard HTML img element. This makes it safe to use with any image data, including screenshots, documents, or private photos.