Convert BMP to AVIF

Converting BMP to AVIF is worth doing when the destination matters more than the source. BMP is built for uncompressed bitmaps, mostly a legacy Windows format. AVIF is built for the smallest modern web images, at the cost of slower encoding. Which one you want depends entirely on where the image is going next.

The largest possible size reduction from the largest possible starting point. An uncompressed BMP converted to AVIF can lose well over ninety five percent of its size. Support is the limitation, so this suits web delivery rather than sharing.

AVIF compresses by discarding detail, so this conversion trades some fidelity for a much smaller file. At high quality settings the difference is invisible in photographs, though flat colour and sharp text can show artefacts. Keep the BMP original as your master copy.

BMP stores pixels uncompressed, which is why the files are so large. Expect a dramatic size reduction here, frequently by a factor of ten or more, with no visible change.

AVIF compresses harder than anything else here, so coming from a lossless source the reduction can be dramatic. The cost is encoding time and narrow support. Use it for web delivery, and keep the lossless original as your master rather than treating the AVIF as an archive copy.

BMP needs almost no decoding at all, since the pixels are stored raw. That makes it the fastest input here to read and the slowest to encode from, because there is a great deal of uncompressed data to work through.

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