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Formats & playback 4 min read

PNG to JPG Turns the Background Black

Transparent pixels turn black or white after PNG → JPG because JPG has no alpha channel at all — the transparency has to land somewhere.

Which formats carry alpha

Alpha-capable: PNG, WebP, AVIF (GIF: single-bit). Not capable: JPG. Direction rule: alpha → non-alpha always flattens onto a fill color; the reverse loses nothing.

If you need transparency and smaller files, WebP/AVIF beat PNG — mind legacy compatibility for WebP.

Convert the right way

Flatten onto white (or your design color) before converting to JPG. Keep the PNG original for logos and design assets; export a JPG copy per channel that requires it.

Quality tier for batch conversion

85–90 is the sweet spot for photos; text and line art reveal JPG artifacts first, so check edges after conversion. Converting to WebP/AVIF keeps alpha and cuts size by 25–35% or more.

Frequently asked questions