Convert BMP to HEIC — Free & Private

How much quality is lost when converting BMP to HEIC?

BMP stores every pixel exactly with no compression, so the HEIC conversion is the first time any lossy compression is applied — there's no prior generation of loss to compound. At a quality setting of 85–90, that first lossy pass is invisible for photos at normal viewing sizes. Fine text and sharp geometric edges are the areas most likely to show subtle fringing if the quality is set too low, so use a higher setting (90–95) for graphics with crisp lines or small text.

• Photos at quality 85–90: no visible difference from the BMP at normal sizes
• Text and sharp edges: use quality 90–95 to avoid visible fringing
• Once converted, the discarded detail can't be recovered — keep the BMP if it's a master
• Recommended quality: 85 for general web use, 90–95 for print or detailed graphics

What happens to transparency when converting BMP to HEIC?

HEIC supports an alpha channel, but most BMP files don't carry meaningful transparency to begin with — BMP is typically used for fully opaque images. If your BMP does include alpha data (some 32-bit BMPs do), check the converted HEIC carefully, since how well that transparency survives depends on the encoder and the app viewing the file. For images where transparency matters, PNG and WebP have far more consistent support than either BMP or HEIC.

• HEIC supports alpha channel transparency in principle
• Most BMP files are fully opaque with no transparency to preserve
• If your BMP has 32-bit alpha data, verify it survives the conversion
• For reliable transparency, PNG or WebP are safer choices than HEIC

What HEIC quality setting gives the best size-to-quality trade-off?

Quality 85 is the standard sweet spot — it captures nearly all the visual detail of the BMP while cutting file size dramatically, since you're going from an uncompressed format to one of the most efficient codecs available. For thumbnails or previews where size matters most, 70–80 is common. For images headed to print or large displays, 90–95 keeps fine detail crisp. Quality 100 is rarely worth it — it produces a much larger file for a difference almost no one can see.

• Quality 85: strong all-purpose default — high quality, big size reduction
• Quality 70–80: thumbnails, previews, social media images
• Quality 90–95: print, large displays, detailed product photography
• Quality 100: rarely needed — large file size for minimal visible benefit

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

Very significantly — typically 90% or more smaller. Since BMP stores pixel data essentially uncompressed, even a modest HEIC quality setting represents a huge reduction. A 6MB BMP photo can easily become a 300–600KB HEIC at quality 85 with no visible difference in normal viewing. The size drop is largest for photos; simple flat-colour graphics still shrink substantially, just by a somewhat smaller margin.

• Photos: often 90%+ smaller than the original BMP at quality 85
• Screenshots and UI graphics: large reductions, though less extreme than photos
• A 6MB BMP can realistically become a 300–600KB HEIC
• Images with fine text: use a higher quality setting (90+) to keep edges sharp