BMP to Base64

Drop a BMP and get a Base64 data URI you can paste straight into HTML or CSS. Everything runs in your browser — the file is never uploaded.

Drop a BMP here or click to browse

BMP files

— —

DATA URI

Raw Base64 Copy

Base64 output

Waiting for a BMP

How to convert a BMP to Base64

Drag a BMP onto the drop zone above (or click to browse). The tool reads it locally with the browser's FileReader API and produces a data URI — a string of the form data:image/bmp;base64,Qk… that embeds the whole image inline. Click Copy, then paste it where you need it. Use the Raw Base64 toggle if you want only the encoded payload without the data: prefix.

When to inline a BMP as a data URI

BMP is a lossless, uncompressed format — every pixel is stored raw — so bitmaps are large before you even encode them. That makes them a poor fit for inlining. The tradeoffs:

• Size: BMP is uncompressed, and Base64 adds another ~33% on top. A raw bitmap becomes a very long data URI fast.
• Better formats: Convert the bitmap to PNG (lossless) or WebP (smaller) first — you'll get a fraction of the byte count for the same pixels.
• Rule of thumb: only inline a BMP for a tiny icon where the extra bytes don't matter; otherwise compress it first or keep it as a normal file.

Using the data URI in HTML and CSS

In HTML, drop it into an <img> src:

<img src="data:image/bmp;base64,Qk2eAAAAAAAAADYAAAAo..." alt="bitmap">

In CSS, use it as a background-image:

.bitmap {
  background-image: url("data:image/bmp;base64,Qk2eAAAAAAAAADYAAAAo...");
}

Is this private?

Yes. The conversion happens entirely client-side in JavaScript. Your BMP is read into memory in the browser and encoded locally — it is never sent to a server. You can confirm this by opening DevTools → Network: adding a BMP fires no upload request.

Frequently asked questions

How do I convert a BMP to Base64?

Drop the BMP onto the converter at the top of this page. It outputs a data URI like data:image/bmp;base64,Qk… that you can paste into an <img> src or a CSS url().

Does converting a BMP to Base64 increase its size?

Yes — twice over. BMP is already uncompressed, and Base64 adds another ~33% because it represents every 3 bytes with 4 ASCII characters. Compressing to PNG or WebP first gives a much smaller result.

Should I inline a BMP as a Base64 data URI?

Rarely. Convert the bitmap to PNG or WebP first, then inline that — an uncompressed BMP produces a needlessly large data URI. Inlining a raw BMP only makes sense for a tiny icon.

How do I go the other way (Base64 back to a BMP)?

Use the Base64 to BMP tool to decode a data URI or raw Base64 back into a viewable, downloadable BMP.