Problems · Conversion surprises
Why Does Converting JPG to PNG Increase File Size?
This is one of the most confusing conversion results. Lossless PNG protects what you have; it doesn’t restore what JPEG threw away, and it rarely shrinks a photo.
Problem: JPG → PNG makes a bigger file and people expect a quality upgrade.
Solution: Use JPG → PNG when you need a lossless working copy or transparency workflow — not to “improve” a photo or shrink it. For smaller web photos, stay on JPG or go to WebP.
Why the PNG is bigger
JPEG packed the image lossily. PNG re-packs decoded pixels without that lossy shortcut, so disk size often rises.
Quality myth
The PNG won’t look sharper than the JPG you started from. It can stop further JPEG generation loss on future edits.
Better paths
Need smaller? Compress JPG or convert to WebP. Need transparency later? PNG/WebP from a better master than a crushed JPG when possible.
Fix it in three steps
- Convert only if you need PNG. Open JPG → PNG for a lossless working copy.
- For web size. Prefer JPG compression or JPG → WebP instead.
- Keep masters. Archive camera/HEIC/PNG originals when you have them.
Open the relevant converter
Convert privately in your browser — nothing is uploaded to a remote queue.
Related tools & guides
Related problems
FAQ
Why does converting JPG to PNG increase file size?
PNG stores pixels losslessly after decoding the JPG, so files often grow. It does not restore JPEG detail. Use PNG as a working copy; use JPG/WebP when you need a smaller photo.
Should I convert PNG back to JPG to shrink again?
You can for delivery, but you’ll add another lossy step. Prefer converting from the best master once.
Why this works locally
- No third-party converter queue — processing stays in this browser
- Convert a delivery copy — keep your master
- Same privacy-first engine as the rest of Format Convertly
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