Image to BMP Converter

Convert PNG, JPG, or WebP images to uncompressed BMP bitmap format for legacy applications.

Tested tool guide Tested browser tools Checked August 16, 2026

What Image to BMP Converter does and how it behaves

Image to BMP Converter creates an uncompressed .bmp file from a selected PNG, JPG, or WebP image. Once a source file is chosen, it decodes the picture in the browser and prepares the BMP for download; the image is not uploaded. This changes the storage format, but it cannot restore detail already discarded by lossy compression. The usual surprise is file size. A small JPG or WebP may expand sharply because its compressed representation becomes uncompressed pixel data, with BMP headers and scanline padding adding more bytes.

How the result is produced

Source conversion

Choose a PNG, JPG, or WebP file using the image input. The converter decodes that image locally in the browser and produces a downloadable file with a .bmp extension. Conversion operates on the decoded picture, so the source compression stream is not embedded inside the BMP. Keep the original file if you may need its source encoding, metadata, or compression settings later.

BMP structure

A BMP file contains a file header, a DIB header, and pixel data; some variants also contain color tables or channel masks. In common uncompressed layouts, scanlines are padded to four-byte boundaries. File size therefore includes more than the visible pixels. Header values describe dimensions and storage characteristics, and the destination program must support the particular BMP representation it receives.

Good uses

Preparing a logo supplied as PNG for an older desktop application whose documented import formats include BMP but exclude PNG, JPG, and WebP.
Turning a WebP reference image into an uncompressed BMP fixture for testing a BMP reader, file detector, thumbnailer, or legacy image-import path.
Converting a JPG scan for a device, emulator, archival workflow, or Windows-era program that specifically requests a file with BMP bitmap structure.

Limits and checks

Do not interpret a larger output as added detail. Uncompressed storage records the already-decoded pixels less compactly, and BMP headers plus row padding contribute additional bytes.
Check transparent areas in the destination application. BMP variants can represent alpha information, but support differs, especially among older readers. Transparency may be ignored, flattened, or displayed differently from the PNG or WebP source.
A .bmp extension does not guarantee acceptance by every BMP-consuming program. BMP covers multiple header versions, bit depths, channel arrangements, and orientation conventions. Validate the downloaded file in the exact application or device that will consume it.

Common questions

Will converting a JPG to BMP improve its quality?

No. The BMP stores pixels decoded from the JPG, including any blocking, ringing, color loss, or softened detail already introduced by JPEG compression. Uncompressed output avoids another compressed BMP representation, but it cannot recreate discarded image information. Keep a higher-quality original if later editing or another conversion is expected.

Will the converted BMP preserve transparency?

Do not assume so. BMP has representations that can carry alpha data, but many legacy applications expect opaque bitmap pixels or ignore alpha information. Inspect transparent edges and fully transparent regions in the intended destination. If transparency is required and that program supports PNG, the original PNG is generally the safer master file.

References and verification

The behavioral notes were checked against the browser implementation. Standards and primary references below define the relevant format, formula, or platform behavior.