Open the HEIC photo in Preview and export a separate JPEG. Keep the original, then check that the new copy opens and meets the recipient’s requirements.
You do not need to convert your whole collection because one website rejects one picture. I would make one trial copy first and stop when it does the job.
What you need
A Mac, its Preview app and an HEIC file saved on the computer. These instructions start with a file in Finder, not a picture still waiting to download from a cloud library.
HEIC is a filename ending commonly used for HEIF photographs. JPEG files often end in .jpg or .jpeg. They are different ways of storing a still image; an unsupported format does not automatically mean the photograph is damaged.
1. Check what the recipient needs
Read the upload requirements or ask what file type the recipient can open. Note any limit on megabytes, pixel dimensions or print shape as well as the requested format.
A JPEG will not necessarily fix an oversized attachment or choose the right print crop. Write the small goal clearly: “One JPEG that opens in this application.”
Choose a photograph with a face or other recognisable detail for your trial. Keep the source in its usual place and decide where the outgoing copy will go.
2. Open the source in Preview
In Finder, locate the HEIC file. Control-click it, choose Open With, then Preview. Check that it is the intended photo before continuing.
If Preview cannot open it, pause and check that the file downloaded fully. Do not change the filename ending from .heic to .jpg: that changes the label, not the picture’s actual format.
Keep any related files together. A still JPEG alone is not a way to preserve the motion of a Live Photo or convert a video.
3. Export a separate JPEG
In Preview, choose File > Export. Open Format and choose JPEG.
Give the copy a distinct name, such as “Birthday-014-sharing”, and choose a destination you can find again. Leave the original unchanged.
Preview offers a JPEG quality control. Begin towards the higher-quality end, then check whether the result meets your actual size limit. There is no single best setting for every photograph and destination.
Select Save. If asked to replace an existing file, cancel and choose a new name. It is easier to compare two clearly named attempts than recover a copy you accidentally overwrote.
4. Open and compare the new file
Go to the destination in Finder and open the JPEG itself. Check the whole picture, then inspect a face, lettering or a patterned area at a useful size.
Look for the expected orientation, crop and colour. Compare at similar viewing sizes; a small thumbnail can hide obvious damage. Check the image information against any required pixel dimensions, not just the storage size.
If it is too large, return to the original and export another trial with adjusted quality. Avoid repeatedly resaving the same JPEG while guessing. Keep the version that meets the requirement and still looks acceptable.
Check your result
Confirm that the JPEG opens, shows the whole intended picture and leaves your original available. For an upload, inspect the receiving site’s preview before placing an order or making anything public.
If a recipient still cannot open it, check that you selected the new JPEG, rather than the original from a recent-files list. Record the receiving app and error if the problem continues.
Conversion does not guarantee that captions, location information or every source feature will be preserved or removed. Inspect the outgoing filename, visible addresses and accompanying message separately. An online converter also introduces an upload to another organisation; Preview avoids needing that extra service for this task.
Next step
Check location details before sharing from an iPhone if that is where you will send the copy. Recheck the options for the actual route you use.
Sources and scope
Researched 9 September 2026: Apple’s Preview conversion instructions and HEIF and HEVC guidance. This is documented guidance with editorial checks, not a hands-on conversion test.