Why did my transparent background disappear after converting to JPG?

JPG simply has no transparency — that is the format's rule, not a limit of ours. Transparent areas get filled with white on the way over. Convert to PNG or WebP if you need to keep transparency.

Why does the quality slider do nothing when I pick PNG?

Because PNG is lossless: there is no «Quality» setting to give — it either keeps the pixels exactly or it is not a PNG. The slider stays on screen but has no effect on PNG. To trade quality for file size, choose JPG or WebP.

PNG, JPG or WebP — which should I pick?

PNG when you need transparency or lossless fidelity (screenshots, icons, line art); JPG for plain photos where the smallest file wins; WebP when you want both — usually smaller than JPG at the same perceived quality while keeping transparency, at the cost of browsers from a decade ago not recognising it.

Is it free? Are my images uploaded?

Free, no sign-up, no usage limit. Nothing is uploaded either — it all runs in your own browser.

Convert image formats in bulk

PNG / JPG / WebP, no file cap. Local processing, nothing uploaded.

or start a blank document

Batch conversion tends to come from something specific: a pile of HEICs out of the photo library that you can't send anywhere, a handover that insists on PNG, a site moving JPG to WebP to save bandwidth. Doing them one at a time isn't realistic — and this was never work that needed a person watching it.

The three target formats each involve a trade-off. PNG is lossless and keeps transparency, but the files are the largest. JPG is far smaller, at the cost of lossy compression and no transparency — transparent areas get filled with white on the way over. WebP sits between them: usually smaller than JPG at the same perceived quality while keeping transparency, though browsers from a decade ago do not know it. The quality slider runs from 10% to 100% (default 92%) and is always shown, but it only affects JPG and WebP; PNG is lossless and has no quality setting, so moving it changes nothing. There is no cap on the number of files — how many you can convert depends on your computer. Converted files download one by one, each triggered slightly apart from the next, because browsers block downloads fired back to back. It all runs in your own browser; the images are never uploaded.

Key features

Three target formats

PNG lossless with transparency, JPG smallest but opaque, WebP a bit of both.

Quality is adjustable

Quality slider from 10% to 100%, default 92%; it only affects JPG and WebP — PNG is lossless and ignores it.

No cap on files

Convert as many as you pick — the limit is your computer, not a gate we set.

Runs locally

The images are never uploaded. Close the tab and nothing is left.

How to use

1
Pick the images

Select hundreds at once — there is no limit on the count.
2
Choose the target format

PNG, JPG or WebP. Avoid JPG if you need transparency.
3
Set quality (optional)

Quality slider from 10% to 100%, default 92%; it only affects JPG and WebP.
4
Collect them from Downloads

They arrive one by one; your browser may first ask whether to allow multiple downloads.

FAQ

Why did my transparent background disappear after converting to JPG?: JPG simply has no transparency — that is the format's rule, not a limit of ours. Transparent areas get filled with white on the way over. Convert to PNG or WebP if you need to keep transparency.
Why does the quality slider do nothing when I pick PNG?: Because PNG is lossless: there is no «Quality» setting to give — it either keeps the pixels exactly or it is not a PNG. The slider stays on screen but has no effect on PNG. To trade quality for file size, choose JPG or WebP.
PNG, JPG or WebP — which should I pick?: PNG when you need transparency or lossless fidelity (screenshots, icons, line art); JPG for plain photos where the smallest file wins; WebP when you want both — usually smaller than JPG at the same perceived quality while keeping transparency, at the cost of browsers from a decade ago not recognising it.
Is it free? Are my images uploaded?: Free, no sign-up, no usage limit. Nothing is uploaded either — it all runs in your own browser.

Try Convert image formats in bulk now

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