Convert JPG to BMP using a pure JavaScript BMP binary writer. Generates valid 24-bit DIB BMP files with correct BITMAPFILEHEADER and BITMAPINFOHEADER. No quality loss in the BMP output — pixels are written exactly. Batch up to 10 files.
Click or drag up to 10 JPEG or JPG files. Each will be converted to a standard 24-bit Windows BMP file compatible with Paint, Photoshop, and all image editors.
Each JPG is decoded to raw pixels and the BMP binary is constructed in your browser. Note that BMP files will be significantly larger than the original JPG — BMP stores pixels uncompressed.
Download each BMP individually. The output is a valid 24-bit BMP with BITMAPFILEHEADER and BITMAPINFOHEADER — compatible with all Windows and cross-platform software.
BMP files are required when: working with legacy Windows applications that only accept BMP, creating Windows cursors or icons (ICO files contain BMP data), some CAD and engineering software requires BMP input, certain industrial machine vision systems only accept BMP, and when you need a completely uncompressed pixel representation for image processing algorithms.
BMP stores every pixel as raw colour data. A 1920×1080 image at 24-bit colour = 1920 × 1080 × 3 = 5.93 MB. The same image compressed as JPG at quality 85 is typically 300–600 KB. BMP has no compression — the file size is determined purely by width × height × bit depth. This is expected behaviour; use BMP only when required by your software.
This tool generates 24-bit Windows DIB (Device-Independent Bitmap) format — the most widely compatible BMP variant. The file structure: BITMAPFILEHEADER (14 bytes) + BITMAPINFOHEADER (40 bytes) + pixel data (stored bottom-to-top as per BMP spec). This is compatible with Paint, Photoshop, GIMP, and virtually all image software that accepts BMP.
Yes — the conversion path is JPG → browser canvas (24-bit RGB) → BMP binary. The canvas decodes the JPG and this tool writes the exact RGB values to the BMP. Note that the JPG was already lossy-compressed before this conversion — the BMP is a lossless representation of the JPG pixels, but any JPG compression artefacts from the original encoding are preserved in the BMP.
BITMAPINFOHEADER is the 40-byte structure that defines the BMP image properties: width (4 bytes), height (4 bytes, negative for top-to-bottom), bit depth (2 bytes, we use 24), compression (4 bytes, 0=none), image size (4 bytes), pixels per metre X and Y (4 bytes each), colours used (4 bytes), and important colours (4 bytes). The 14-byte BITMAPFILEHEADER preceding it contains the file signature ("BM"), file size, and offset to pixel data.
Yes — use the BMP to JPG Converter tool on this hub to convert back. However, each JPG re-encoding cycle reduces quality slightly (generation loss). For workflows that require multiple conversions, keep a master PNG (lossless) and only produce JPG or BMP as final output formats.
