Why convert HEIC to PNG
PNG is occasionally demanded outright: a design tool that will not import HEIC, a print workflow, an upload form that lists PNG and nothing else. When that is the situation, this is the conversion you need and it works exactly as expected. It is worth knowing what you are getting, because the internet is full of advice suggesting PNG "preserves quality". HEIC is a lossy format. Your phone discarded detail when it saved the file, and that detail is gone before any converter sees it. PNG will preserve what remains perfectly — which is not the same thing as improving it. What you end up with is a lossless container wrapped around already-lossy data: faithful to the HEIC, many times its size, and visually identical to a JPG a fraction as large.
What this conversion costs you
- The file gets dramatically larger. A 2 MB HEIC commonly lands somewhere between 10 and 25 MB as PNG. PNG records every pixel exactly and compresses only by finding repetition; a photograph is mostly detail that does not repeat, so there is very little for it to find. This is the single reason not to do it casually.
- No quality is recovered. Nothing here can restore what the phone already threw away. Converting to a lossless format after the loss has happened preserves the loss perfectly.
When not to do this
Avoid this if you simply want the photo to open on Windows or attach to an email — convert to JPG instead, which does the same job at a fraction of the size and looks the same. PNG is the right target only when something specifically demands it, or when you need exact pixels for editing and the extra size genuinely does not matter.
Common questions
Why is my PNG so much larger than the HEIC?
Because PNG is lossless and HEIC is not. HEIC achieves its small size by discarding detail your eye is unlikely to miss; PNG stores every remaining pixel exactly. A photograph has millions of pixels that do not repeat, so PNG has very little to compress. Ten to twenty times the original size is normal.
Does converting HEIC to PNG improve the quality?
No. The quality was fixed when your phone saved the HEIC, and the detail it discarded cannot be recovered by any later conversion. PNG preserves what is left without further loss, which is useful if you are about to edit the image repeatedly, but it does not make the picture better.
Should I use PNG or JPG for an iPhone photo?
JPG, unless something specifically requires PNG. For a photograph the two look the same at sensible quality settings and the JPG is far smaller. Choose PNG when the image has sharp edges and flat colour — a screenshot, a diagram, a logo — or when a form insists on it.