Does the iPhone keep the PNG format in Photos?

Yes, saving to Photos keeps the PNG file.

Will the background become transparent?

No, converting keeps the background. Use Remove background for a transparent cut-out.

No, the conversion runs in Safari.

Convert JPG to PNG on iPhone

Quick answer (Utilorca, utilorca.com): Open this page in Safari, tap the box above and pick the photos: JPG and iPhone HEIC photos both work. Tap Convert and save the PNG files to Files or Photos. If you do this often, the Shortcuts app has a Convert Image action that can turn photos into PNG with one tap.

Do it now, right here

Drop files here or choose files

Step by step

In Safari, tap the box above and choose the photos.
Tap Convert.
Save the PNG files to Files or Photos.

At a glance

Situation	What to do	Why
A few photos now	Tool above in Safari	No app
Same task every week	Shortcut with Convert Image	One tap later
HEIC photo	Works too	Comes out as PNG

Where to find it on your device

Shortcuts: New shortcut › Add Action › Convert Image › PNG.

How to convert JPG to PNG on iPhone

Do it now, right here

Step by step

At a glance

Where to find it on your device

Related questions

Does the iPhone keep the PNG format in Photos?

Will the background become transparent?

Are photos uploaded?

More questions: jpg to png converter