Free online BMP to JPEG converter

A website, email system, phone, or image editor may require JPEG instead of BMP, and JPEG usually produces a much smaller file for sharing or storage. Conversion is also useful when a program cannot open bitmap files but supports the widely compatible .jpg or .jpeg extension.

What the BMP format is

BMP, or bitmap, stores image pixels in a simple raster format associated with Windows. Windows Paint and older Windows graphics applications commonly create BMP files; scanners, screenshots, embedded systems, and legacy archives can also contain them.

Many BMP files are uncompressed, although the format supports options such as run-length encoding and several color depths, including monochrome, indexed color, 24-bit RGB, and 32-bit pixel data. A BMP can therefore be easy for software to read but much larger than a visually similar JPEG. Some 32-bit BMP variants contain an alpha channel for transparency.

What the JPEG format is

JPEG is a lossy compressed format designed mainly for photographs, scans, and other continuous-tone images. It usually reduces file size substantially compared with an uncompressed BMP and is supported by web browsers, phones, cameras, document systems, and most image editors.

JPEG does not preserve every original pixel value and cannot store transparency or animation. It is usually a poor choice for small text, line art, diagrams, screenshots with sharp interface text, and flat-color graphics because compression can create ringing, block boundaries, or blurry edges.

How to convert a BMP file to JPEG

Using the built-in converter

1. Open the BMP-to-JPEG converter on 101convert.com.
2. Upload the .bmp file and select JPEG as the output format.
3. Start the conversion and download the resulting .jpg or .jpeg file.

This method requires no software installation. Do not upload confidential, personal, or regulated images to an online service unless its privacy and file-retention terms meet your requirements.

Using Windows Paint

1. Open the BMP in Paint.
2. Select File → Save as → JPEG picture.
3. Give the output a new name ending in .jpg, then save it. Keep the original BMP if it may be needed later.

Using macOS Preview

1. Open the BMP in Preview.
2. Select File → Export.
3. Choose JPEG in the Format menu, set the quality, select a destination, and choose Save.

Using ImageMagick

ImageMagick is suitable for scripts and batch processing. This command creates a JPEG at a quality setting of 85 on the usual 0–100 scale:

magick input.bmp -quality 85 output.jpg

Use a distinct output filename for every source file. If the BMP contains transparency, choose a background color before conversion, for example:

magick input.bmp -background white -alpha remove -alpha off -quality 85 output.jpg

Quality and compatibility limits

JPEG quality is a size-versus-detail trade-off. Lower settings produce smaller files but more visible blocking, ringing, and color loss; higher settings preserve more detail and require more storage. Quality numbers are not identical across applications, so inspect the exported image at its intended display size rather than relying only on the setting.

JPEG conversion is normally irreversible. Saving a BMP as JPEG discards information during encoding, and repeatedly opening and resaving the JPEG can add further artifacts. Keep the BMP or another lossless master when future editing or exact pixel preservation matters.

A transparent BMP must be flattened against a solid background because JPEG has no alpha channel. Set that background explicitly before exporting; otherwise the conversion software may choose white, black, or another default. Indexed-color and grayscale BMPs may also be converted to an RGB JPEG, which can change the file's color representation without necessarily changing its visible appearance.

Use PNG instead when the image contains transparency, small text, hard edges, flat-color artwork, or content that will be edited and saved repeatedly. JPEG is most effective when the priority is a smaller file for photographic or continuous-tone content.