What is a Base64 data URL?

A data URL embeds the file content directly in the URL string using Base64 encoding. It starts with data:image/png;base64, followed by the encoded bytes. Browsers can render it as an image without fetching a separate file.

Why does Base64 make the file larger?

Base64 represents every 3 bytes of binary data as 4 ASCII characters, increasing size by roughly 33%. For large images this overhead is significant; for small icons under 10 KB it's usually acceptable.

Is there a file size limit?

No hard limit, but very large images produce extremely long strings that may be slow to copy or paste. For images above 1 MB, consider compressing first.

Is my image uploaded to a server?

No. The FileReader API reads the file directly from your local disk. No data is transmitted over the network.

Image to Base64

Convert any image file to a Base64 data URL for embedding in HTML, CSS, or JSON.

How to use this tool

1Click the upload zone to browse for an image file (JPG, PNG, WebP, GIF, SVG, or AVIF).
2The Base64 data URL is generated instantly and shown in the output textarea.
3A live image preview below the textarea confirms the encoding is correct.
4Click the Copy button to copy the full data URL to your clipboard.

About Image to Base64

Embedding an image as a Base64 data URL eliminates an HTTP request, which matters for small critical assets like inline icons, email template images, and loading spinners. This tool uses the browser's FileReader API to read your image file and produce the full data URL string in the format data:image/png;base64,iVBORw0K... — ready to paste directly into an HTML src attribute, a CSS background-image property, or a JSON payload. The output textarea shows the complete data URL and a live image preview confirms the encoding is correct. Click Copy to grab the full string. Any image format your browser supports works as input: JPG, PNG, WebP, GIF, SVG, AVIF. The conversion is entirely local — the FileReader API reads the file from disk without any network request. Note that Base64 encoding increases file size by approximately 33%, so this technique is best suited for images under ~10 KB.

Frequently asked questions

Related Tools

Image Resizer

Resize images to exact pixel dimensions in your browser — no upload, no server.

Image

Image Compressor

Compress JPG, PNG, and WebP images client-side using the Canvas API — no uploads, no server.

Image

PNG to JPG Converter

Convert PNG images to JPG in your browser — transparency filled white, quality adjustable.

Image