PNG to JPG Converter (and JPG to PNG)
Convert PNG to JPG with a chosen background colour for transparent areas, or JPG to PNG, in batches of up to 20 — all on your device, nothing uploaded.
In short
PNG to JPG conversion flattens transparency onto a background colour (white by default) and applies lossy compression — quality 85–95 is visually identical and several times smaller; JPG to PNG is lossless but larger and cannot restore detail already lost. Forms that accept only JPG are the usual reason to convert.
Who this is for: Anyone whose form, portal or app wants JPG instead of PNG (or the reverse), in batches.
PNG vs JPG — which to use
- JPG is for photos: lossy compression gives small files, but no transparency — transparent PNG areas are filled with the background colour you choose (white by default; use your page colour for web graphics).
- PNG is lossless and keeps transparency: logos, screenshots, text, line art. Converting a JPG to PNG does not restore lost detail; it just stops further loss and usually makes the file several times larger.
- Forms and portals that "only accept JPG" (job sites, visa applications, exam boards) are the main reason to convert PNG screenshots and scans. If they also impose a KB limit, use the resize-to-KB tool afterwards.
Assumptions
- Canvas re-encode; JPG output flattened on the chosen colour; PNG output lossless.
- Up to 20 files per batch; metadata removed.
- Processed on the device.
Worked example
Converted to JPG at quality 90 on a white background → about 220 KB, same 1920 × 1080 pixels; text stays crisp at 90 but can show faint halos at 70 and below.
Frequently asked questions
Why does my JPG have a black background?
Some converters fill transparency with black; this one uses the colour you set (white by default).
Does converting lose quality?
PNG → JPG is lossy, but at quality 85–95 the difference is invisible for most uses. JPG → PNG is lossless.
Can I convert many files at once?
Yes, up to 20 per batch, with a Download all button.
Is anything uploaded?
No — everything runs in your browser via the canvas API.
How do I convert PNG to JPG without a black background?
Set the background colour (white by default) — transparent areas are filled with it before saving as JPG.
Is JPG smaller than PNG?
For photos, usually 5–10× smaller; for flat graphics with few colours PNG can be smaller and sharper.
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