Your files stay on your Mac.
Convertessa hands each HEIC to libvips, decodes the HEVC-coded still inside it and writes a standard PNG beside it. PNG is lossless, so the decoded pixels go into the file exactly as they came out — nothing is recompressed and no quality setting applies. Drop one photo or a folder of a thousand and the queue works through them on your Mac, with no upload and no account.
Since iOS 11, an iPhone left on the High Efficiency camera setting saves stills as HEIC: a HEIF container wrapping HEVC-coded image data. The container half matters more than people expect, because one .heic file is really a small bundle of items, and PNG is a single-image format.
The primary image at its full pixel dimensions, and its alpha channel if it has one. PNG is lossless, so the decoded pixels are written verbatim — there is no re-encode and no quality setting, because none would mean anything. iPhone photos are usually tagged Display P3, and the ICC profile is written into the PNG so colour-managed apps render it correctly.
.mov.Two practical notes. Orientation first: HEIC records rotation as a metadata flag and PNG has no equivalent, so the rotation is applied to the pixels as the file is written. The picture stands up correctly in every viewer, including the ones that never read metadata. Then size: expect a PNG roughly five to ten times larger than the HEIC it came from. Lossless is expensive, and that is the whole bargain. If you simply need something a browser or a Windows machine can open and the megabytes matter, JPEG or WebP serve better. PNG is the right target when you want exact pixels — screenshots, flat-colour graphics, images with transparency, or anything about to be edited again.
Drag one photo, a Photos export or a whole folder onto the queue. Convertessa picks up every .heic file, including the ones your iPhone named IMG_0001 through IMG_0999, in a single pass.
Select PNG in the output list. No quality setting appears, because there is nothing to trade away — the encoder is lossless and every pixel of the decoded HEIC lands in the file.
Hit Convert. PNGs are written to the folder you chose with the Display P3 profile intact and EXIF removed, so no GPS coordinates or camera serial ride along into a file you share.
Images, audio, video, documents, archives, eBooks and fonts — all converted natively, right on your Mac.
Pick a format you have — see everything Convertessa can turn it into.
Convert hundreds of files at once with per-type group defaults and individual overrides.
First-class support for HEIC, AVIF and WebP — encode and decode, both ways. Read JPEG XL and a dozen more modern formats too.
Drop files anywhere on the window. Native, instant, and exactly what you’d expect on a Mac.
Dial in compression, resolution and bitrate. Keep originals pristine or shrink for sharing.
Never overwrite a file by accident. Convertessa appends safe suffixes automatically.
Every job is logged locally. Re-run a previous conversion or revisit recent outputs in a click.
Bundle your converted files straight into a single ZIP, TAR or 7z — packaged and ready to share the moment a job finishes.
Right-click any file in Finder and choose Convert. A Quick Action handles it on the spot — no need to open the app first.
Shrink Convertessa to a tidy mini window that tucks into a corner — just a drop zone and a format picker for quick, one-off conversions.
No cloud. No account. No upload. Every conversion happens entirely on-device, using the power already in your Mac. What you convert is nobody’s business but yours.
Script conversions, wire them into your build, or batch a folder from the terminal. The same engine, no GUI required.
Read the full CLI documentation →Shrink Convertessa down to a small, focused window — drop, convert, done, with your recent conversions one click away.
macOS 14+ · Apple Silicon & Intel
New formats, new features, and fixes — every release, on the record.
Because you are trading compression for exactness. HEIC stores the picture with HEVC, a modern lossy codec that discards detail your eye is unlikely to miss; PNG keeps every pixel and only squeezes the result with a lossless algorithm. A 2 MB iPhone photo commonly lands somewhere between 8 MB and 20 MB as a PNG. That is expected rather than a fault — if size matters more than pixel-for-pixel exactness, JPEG or WebP is the better target.
No. Recent iPhones store an HDR gain map alongside the main image — an auxiliary picture that tells a capable display how far to lift the highlights. PNG has no place to store it, so the PNG is the standard-dynamic-range base image. Side by side on an HDR screen the original will look brighter and punchier. The base rendition is complete and correct in itself; it simply will not glow.
iPhone photos are usually tagged Display P3, a wider colour space than sRGB. That ICC profile is written into the PNG, so colour-managed software — Preview, Safari, Photoshop, Affinity — renders it accurately. Software that ignores embedded profiles treats P3 numbers as though they were sRGB, and reds and greens come out too vivid. The file is right; the viewer is not. For a profile-blind pipeline, convert to sRGB in an editor before handing the image over.
It is dropped. A Portrait shot keeps auxiliary items inside the HEIC — a depth map and a person segmentation matte — which is how Photos can re-render the background blur months later. PNG holds one image, so only the primary picture converts, carrying whatever blur was already baked into it. If you might still want to adjust the effect, keep the HEIC as your master and treat the PNG as a delivery copy.
Yes, and be specific about how. File → Export → Export Unmodified Original gives you the real HEIC files; the plain Export command hands you JPEGs, which makes the whole exercise pointless. Once they are on disk, point the app or the CLI at the folder:
convertessa ~/Desktop/Originals/*.heic --to png -o ~/Pictures/PNG
Yes. HEIF can carry an alpha channel — stickers, images exported from design tools and some app-generated captures have one — and PNG is among the few widely supported formats that stores transparency losslessly. The alpha channel is written through with the colour channels: nothing is composited underneath, no white rectangle appears. When a HEIC has transparency at all, PNG is usually the reason you are converting in the first place.
Yes. HEIC records orientation as a metadata flag and expects the viewer to honour it; PNG has no such flag, so the rotation has to be applied to the pixels themselves as the file is written. The result stands upright everywhere, including in software that never reads metadata. One side effect worth knowing: the PNG's stored width and height are swapped relative to the HEIC for any photo taken in portrait orientation.