Is my PNG uploaded to a server?

No. The image is read locally by the browser FileReader API and the Base64 string is printed on the same page. The image bytes never leave your device.

Should I inline every image as Base64?

No. Inlining works best for small images under about 5 KB, such as icons and simple logos. Larger images bloat your CSS or HTML by roughly 33 percent and cannot be cached separately by the browser.

PNG to Base64 Converter Online - Free, No Upload

Select PNG For Base64 Encoding Select Image

Pick a PNG above and you get its Base64 string right away, plus two snippets you can paste as they are: an HTML img tag and a CSS background-image rule. Copy any of them with one click.

Nothing is uploaded. Your browser reads the file and does the encoding on your own machine. That means no size cap, no queue, and no signup. It is free.

How to Convert a PNG to Base64

Click Select Image and pick your PNG.
The preview and the code blocks appear underneath.
Hit Copy To Clipboard on whichever block you need.

The tool takes JPG, WebP, GIF and SVG too, so you do not need a different page for each type.

Three Snippets, Ready to Paste

Most people want the string in one of three shapes, so the tool prints all three.

HTML - a full img tag with the data URI already in the src.
CSS - a background-image: url(...) rule for your stylesheet.
Base64 code - the data URI on its own, for JSON fields, config files, or an API.

The data URI starts with data:image/png;base64,. Some APIs want that prefix stripped off. If yours rejects the string, that prefix is the first thing to check.

When Inlining an Image Helps, and When It Hurts

Inlining saves an HTTP request. For a tiny icon that is a real win, because the request costs more time than the bytes do.

It stops being a win fast. An inlined image cannot be cached on its own, so every page load carries it again. It also blocks your CSS file from finishing its download while the browser reads past all that text.

Our rule of thumb after building these pages: inline under 5 KB, link anything bigger. Icons, bullets and simple logos yes. Photos and hero images no.

Your PNG Stays On Your Device

Most online converters send your image to a server, encode it there, and send the text back. This page does the opposite. The PNG is read by JavaScript in your own browser using the FileReader API. The pixels never travel anywhere.

So there is no copy of your image sitting in someone's upload folder, no account to make, and no email to hand over. Open the tab, convert, close the tab.

PNG to Base64 vs Linking the Image File

Base64 turns every 3 bytes into 4 characters. The string is always about 33% bigger than the PNG it came from. A 12 KB icon becomes roughly 16 KB of text.

You are trading size for one fewer request. That is worth it for small images and clearly not worth it for big ones. Gzip claws some of the bloat back, but not all of it.

Turning a Base64 String Back Into a PNG

If you have the string and want the picture, use the Base64 to image decoder. Paste the text, see a preview, download the PNG.

For other file types, file to Base64 handles any format, and PDF to Base64 adds a ready iframe embed snippet.

Common Questions

Does converting a PNG to Base64 lose quality?

No. Base64 is an encoding, not compression. Every byte survives, so the decoded image matches the original pixel for pixel.

Is my PNG uploaded anywhere?

No. Your browser reads the file and prints the string on the same page. Nothing goes over the network. Open your browser network tab and you will see no request.

Does it work with transparent PNGs?

Yes. The alpha channel is part of the file bytes, so transparency is kept exactly. The decoded image still has its see-through areas.