How much smaller will the HEIC be compared to the BMP?

BMP files are uncompressed - They can be enormous even for relatively small images. A 1920×1080 BMP file is approximately 6 MB; the equivalent-quality HEIC is typically 100–300 KB. Converting BMP to HEIC provides the most dramatic space savings of any conversion on this site (routinely 95%+ reduction) with minimal visible quality impact at settings of 85%+.

BMP files commonly appear in Windows development contexts, screensavers, paint program output, and legacy software that saves images in uncompressed format. They are also produced by some industrial and scientific instruments, screen capture tools, and older scanners. Converting to HEIC makes these files practical for long-term archiving - Especially in Apple Photos or iCloud where HEIC is the native currency.

BMP does not support transparency, so no alpha handling is needed during conversion. The pixel data maps directly to the HEVC encoder. Keep in mind the usual HEIC caveat: the output opens natively on Apple devices, but Windows needs the HEVC Video Extensions codec - If the files must return to a legacy Windows workflow, JPG or PNG may serve better.

Reasons to convert BMP to HEIC usually come down to compatibility, file-size, or specific feature requirements. Common situations:

• An app or platform only accepts HEIC uploads.
• You need a feature unique to HEIC (e.g. transparency, vector scaling, animation, multi-page pages, etc.) that BMP doesn't provide.
• You're optimising file size — modern formats often produce smaller files than the older format you started with.
• You need a single archival format across a project so files behave consistently in the same viewer.

1. Open the BMP → HEIC tool on heic.now.
2. Drag your BMP file onto the drop zone, or click Select files. You can drop a whole folder of files at once.
3. The output is fixed to HEIC. If the format supports extra options (page size, transparency background, quality, EXIF stripping), tweak them in the right-hand panel.
4. Click Convert. The job runs on our server and finishes in a few seconds for typical photos.
5. Download the result. Files stay in storage for 24 hours and are then permanently deleted.

The entire flow is free for the first 10 jobs per day with no signup required. A free account doubles that quota; a premium plan removes the limit entirely.

• Quality 85% is sufficient for most BMP-to-HEIC conversions - BMP files typically contain photographic or screengrab content that HEVC handles well.
• If the BMP was created from a screenshot or UI content with crisp text edges, convert to PNG instead - Lossless output preserves sharp text better than any lossy encoder.
• Converting for archival? Spot-check a few converted files on the devices you'll actually view them on - HEIC support outside Apple hardware varies.