An upload form says PNG only. Or you are editing a screenshot-style image in an app that wants lossless files. Or a colleague asked for a PNG and all you have is the JPG your camera made. The conversion itself takes a few taps. What is worth knowing first is what PNG will and will not do for you.

JPG and PNG, side by side

At a glance

Cost
Free, forever
Account
None needed
App Store
No install
Runs on
iPhone, via Shortcuts
JPGGrabioPNG
JPG in, PNG out, on your iPhone
JPEG and PNG compared, from MDN “Image file type and format guide” (read 8 Nov 2026)
JPG (JPEG) PNG
Compression Lossy Lossless
Transparency (alpha channel) Not supported Full alpha transparency supported
What MDN says it suits Photographs. Lossy compression on sharp content like diagrams or charts can look poor Lossless graphics, with more colour depth options than GIF

Two things follow from that table, and both save you time.

How to Convert JPG to PNG on iPhone

JPG to PNG: the detail already lost stays lostA box labelled JPG with detail already removed by lossy compression points to a box labelled PNG that stores those pixels without loss.JPGlossy, no alpha channelPNGlossless, alpha capable

It will not bring back detail. The JPEG was already lossy when your phone saved it. Converting to PNG stores those pixels without further loss, but it cannot recreate what was thrown away the first time.

It will not make the background transparent. JPEG has no alpha channel, so the converted PNG has nothing transparent in it. PNG can carry transparency, but a JPG has none to carry across.

What you do get is a file in the format a form or app asked for, and a format that does not lose more quality each time you re-save it.

PNG usually takes more space than the JPG it came from, because it keeps every pixel. I have not measured that on a set of photos, so check the size on yours before you send it somewhere with a limit.

How to do it with Grabio

  1. Add Grabio to your iPhone once, it’s a free Apple Shortcut. Get the free Shortcut here.
  2. Open the JPG in Photos or Files and tap Share.
  3. Tap Grabio in the share sheet.
  4. Choose Photo → PNG from the photo menu.
  5. Grabio converts it with Apple’s own convert action inside the Shortcut and saves it to your Photos library. It shows “Done, saved to your Photos” when it finishes.
Grabio photo options relevant here, from the current Shortcut build (v56), read 8 Nov 2026
Option What it does Where it saves
Photo → PNG Converts the photo to PNG Photos
Photo → JPG Converts the photo to JPG Photos
Compress photo Small, Medium or Large JPEG Photos
Resize (1080) Resizes the photo to 1080 pixels Photos

If the PNG turns out too big

That is the usual catch. A PNG made from a photo can be much larger than the original JPG. If a form has a size limit, you have two ways down: resize the picture, or go back to JPG.

The options are covered in how to reduce PNG size on iPhone, and the reverse conversion is in how to convert PNG to JPG on iPhone.

Other formats that end up as PNG

If your starting point is a different format, the steps are close but the pages are separate: HEIC to PNG and WebP to PNG.

If you are choosing between formats rather than converting, HEIC vs JPG on iPhone and what the HEIC format is explain what your camera saves by default. More photo guides live in Photo Tools, and how Grabio works sets out which options run on the phone and which open another site.

Get the Shortcut if you convert images more than once. It is free, with no account, and it sits in the share sheet.

Frequently asked questions

Does converting JPG to PNG improve the quality?

No. A JPEG is already lossy when it is saved, so the detail that was removed is gone. PNG stores what is left without further loss.

Will my JPG get a transparent background as a PNG?

No. JPEG does not support an alpha channel, so there is no transparency to carry over. PNG can hold transparency, but the converted image will not have any.

Why is my PNG bigger than my JPG?

PNG uses lossless compression and JPEG uses lossy compression, so a PNG of the same photo usually takes more space. Check the file size on your own image if a form has a limit.

Where does Grabio save the converted PNG?

In the v56 Shortcut, Photo to PNG saves the result to your Photos library.

How do I convert a PNG back to JPG?

Share the PNG to Grabio and choose Photo to JPG. There is a separate guide for it on this blog.

Video is the other half of what Grabio handles for free, see the full video downloader for iPhone comparison if that is what you need next.