When this tool is useful
Modernizing ordinary BMP screenshots, scans, icons, or legacy assets for browsers, documents, and upload forms.
How local processing works
The browser validates the BMP header, dimensions, bit depth and pixel offset, decodes supported uncompressed or documented bitmap layouts to RGBA, then encodes PNG or composites transparency onto the chosen background before JPEG encoding.
How to use it
- Prepare the source and limits: Keep an unchanged source and review the accepted format, dimensions, frame or page budget, and output choices. Modernizing ordinary BMP screenshots, scans, icons, or legacy assets for browsers, documents, and upload forms.
- Process locally: Run the documented bounded operation in this browser and stop when the decoder reports an unsupported structure. The browser validates the BMP header, dimensions, bit depth and pixel offset, decodes supported uncompressed or documented bitmap layouts to RGBA, then encodes PNG or composites transparency onto the chosen background before JPEG encoding.
- Download and verify: Compare output dimensions and decoded pixels with a trusted BMP viewer, inspect palette colors, alpha edges, row orientation and JPEG background at 100%, and choose PNG if exact hard edges or transparency matter.
Important limitations
Not every BMP variant is supported: OS/2 headers, uncommon masks, RLE modes, embedded JPEG or PNG data, color-managed palettes, damaged offsets, and excessive dimensions may be refused. JPEG is lossy and cannot retain transparency; BMP metadata is not carried forward.
Verify the downloaded result
Compare output dimensions and decoded pixels with a trusted BMP viewer, inspect palette colors, alpha edges, row orientation and JPEG background at 100%, and choose PNG if exact hard edges or transparency matter.
Private by design
Your files stay in this browser. The tool does not upload the source or output to our servers.
Questions and answers
When is this workflow useful?
Modernizing ordinary BMP screenshots, scans, icons, or legacy assets for browsers, documents, and upload forms.
What does local processing do?
The browser validates the BMP header, dimensions, bit depth and pixel offset, decodes supported uncompressed or documented bitmap layouts to RGBA, then encodes PNG or composites transparency onto the chosen background before JPEG encoding.
Which format limits matter?
Not every BMP variant is supported: OS/2 headers, uncommon masks, RLE modes, embedded JPEG or PNG data, color-managed palettes, damaged offsets, and excessive dimensions may be refused. JPEG is lossy and cannot retain transparency; BMP metadata is not carried forward.
How should I verify the download?
Compare output dimensions and decoded pixels with a trusted BMP viewer, inspect palette colors, alpha edges, row orientation and JPEG background at 100%, and choose PNG if exact hard edges or transparency matter.