Inlining tiny images as Base64 data URIs eliminates HTTP requests — but past ~2 KB the 33% overhead costs more than it saves. Convert images to data URIs in seconds, with the size rules you should follow.
Base64 converts binary data into 64 printable ASCII characters so files, images, and keys can travel safely through text-only systems. Here's how it works, step by step.
Base64 turns binary data into ASCII text — handy for data URIs, JWTs, and email attachments, useless for "encryption". Learn the real use cases, the 33% size overhead trap, and decode anything in seconds.
Calculate dimensions and aspect ratios for images and video.
Convert SVG code into a Data URI for use in CSS backgrounds and HTML.
Apply CSS filters like grayscale, sepia, and blur to images.
Create organic blob shapes for backgrounds.
Generate smooth wave dividers for your website.
Add image or text watermarks to your photos.
Ever wondered what's inside a JWT? You can decode the header and payload to see the claims, which is super helpful for debugging authentication.
A two-way Base64 image tool. Switch to "Image → Base64" to turn any image into a single line of text you can embed directly in your HTML or CSS — the secret to faster-loading pages, fewer HTTP requests, and easier-to-manage assets. Or switch to "Base64 → Image" to paste a data URL or raw Base64 string and instantly preview and download the decoded image. Everything runs in your browser, so your files never leave your device.
When encoding, the tool reads your image with the browser's FileReader API and produces a Data URL containing the Base64-encoded bytes. When decoding, it parses a data URL (or sniffs the MIME type of a raw Base64 payload) and renders the result as a live image preview you can save.
Data URLs (defined in RFC 2397) embed content directly in web pages as if they were external resources. Base64 is the encoding scheme that converts binary image data into a text-safe format. Decoding simply reverses the process, reconstructing the original bytes from the text.
Yes. Use the toggle at the top to switch between "Image → Base64" (encode) and "Base64 → Image" (decode). It replaces the need for two separate tools.
They are great for small images because they eliminate an extra server request, which can speed up page load times.
Yes, Base64 encoding increases the data size by about 33%. It's best for small images where that overhead is less than the cost of a separate HTTP request.
The decoder accepts raw Base64 too — it inspects the leading bytes to detect common formats (PNG, JPEG, GIF, WebP, SVG) and renders the image automatically.
Yes, Data URLs are supported by all modern web browsers.
All calculations and data processing for this tool are performed locally in your browser. UtilToolkits does not send any of your data to an external server, ensuring your information remains private and secure.
Drag & drop your file here
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image/* · max 10 MB · paste with Ctrl/Cmd+V
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