Older and device formats
What a phone or a Windows program hands you, turned into something ordinary.
- Convert HEIC to JPGTurn an iPhone photo into a JPEG that everything can open.
- Convert BMP to JPGRe-encode a BMP as a JPEG, which is the right move for a photograph and the wrong one for a screenshot.
- Convert BMP to PNGKeep every pixel of a Windows bitmap and stop paying three bytes each for them.
About these tools
Two kinds of file end up here. One comes off a device that chose a modern format on your behalf: an iPhone saving HEIC because Apple switched the default in 2017, and every recipient since has had to deal with it. The other is the opposite problem, a format so old that it predates the assumption that pictures get compressed at all.
BMP is the clearest case. A Windows bitmap stores three or four bytes for every pixel with no compression worth the name, so a screenshot that would be 200 KB as a PNG arrives as six megabytes of the same picture. Nothing about the image is better for it. The format comes from an era when writing a file quickly mattered more than what it cost to keep.
Converting out of either is lossless in the direction that counts. HEIC holds compressed data that has to be decoded and re-encoded, so a HEIC going to JPEG spends a second generation of loss. A BMP holds raw pixels, so a BMP going to PNG loses nothing at all and usually gives back most of the file.