How much smaller will the JPG be?

For photographic content, a JPEG at quality 90 is typically 5–10× smaller than the source PNG. For graphics with flat colour, the savings are smaller.

What about transparency?

JPEG does not support transparency. Pick a background colour (default white) — transparent pixels will be flattened onto it.

Are my images uploaded?

No. PNG decoding and JPEG encoding both happen on a canvas inside your browser.

Will graphics with hard edges look bad?

Possibly. JPEG is tuned for photos; hard edges (logos, screenshots, text) often pick up ringing artefacts. Stick with PNG for those.

Why is the file still large at quality 90?

Quality 90 keeps fine detail — and detail costs bytes. Lower the slider or scale the image first with the Image Resizer.

Does it work on iPhone?

Yes. Canvas-based encoding works on Safari, Chrome and Firefox on iOS / Android.

PNG to JPG コンバーター

PNGをJPEGに変換。品質調整可能、透明部分の背景色選択可。

PNG file(s) Quality 90 Background colour (for transparency)

Select one or more files to begin.

How to convert PNG to JPG

Pick one or more .png files.
Set the JPEG quality (90 is a safe high-quality default; 75 gives smaller files).
Choose a background colour — transparent pixels will be flattened to this colour.
Press Convert to JPG, then download each result.

Common use cases

Email-friendly photos: shrink a 20 MB phone screenshot to a few hundred KB.
Web upload limits: many sites cap uploads at 2 MB — JPEG quality 80 easily fits.
Photo printing: labs expect JPEG, not PNG.

よくある質問

How much smaller will the JPG be?: For photographic content, a JPEG at quality 90 is typically 5–10× smaller than the source PNG. For graphics with flat colour, the savings are smaller.
What about transparency?: JPEG does not support transparency. Pick a background colour (default white) — transparent pixels will be flattened onto it.
Are my images uploaded?: No. PNG decoding and JPEG encoding both happen on a canvas inside your browser.
Will graphics with hard edges look bad?: Possibly. JPEG is tuned for photos; hard edges (logos, screenshots, text) often pick up ringing artefacts. Stick with PNG for those.
Why is the file still large at quality 90?: Quality 90 keeps fine detail — and detail costs bytes. Lower the slider or scale the image first with the Image Resizer.
Does it work on iPhone?: Yes. Canvas-based encoding works on Safari, Chrome and Firefox on iOS / Android.

Last updated: 2026-05-20 By jarvisbox