Transparent background file formats compared
Last reviewed 2026-09-17. Every competitor figure links to the vendor's own page.
Only some image formats can store transparency. PNG, WebP and AVIF carry a full 8-bit alpha channel and handle soft edges correctly. GIF supports only fully-on or fully-off transparency. JPEG supports none at all, which is why saving a cutout as JPEG fills the background back in.
Format comparison
| Format | Transparency | Compression | Relative size | When to use |
|---|---|---|---|---|
| PNG | Yes, 8-bit alpha | Lossless | Large | The default for cutouts. Universally supported and the safest choice when the file will be handed to someone else. |
| WebP | Yes, 8-bit alpha | Lossy or lossless | Typically 25-35% smaller than PNG | Best for web delivery where you control the pipeline. Supported by all current major browsers. |
| AVIF | Yes | Lossy or lossless | Smallest of the group | Strong compression, but encoding is slower and tooling support is thinner than WebP. |
| GIF | 1-bit only, on or off | Lossless, 256 colours | Small but low fidelity | Avoid for cutouts. Binary transparency produces hard, aliased edges with no partial coverage. |
| JPEG | None | Lossy | Small | Cannot store transparency at all. Saving a cutout as JPEG fills the transparent area, usually with black or white. |
| SVG | Yes, vector | Text, compresses well | Very small for flat art | For logos and line art, not photographs. A photo embedded in SVG is still a raster image. |
Why partial transparency matters
An alpha channel stores how opaque each pixel is, from fully transparent to fully solid. That range is what makes a cutout look natural, because real edges are not binary: a pixel sitting on the boundary of a shoulder is genuinely part subject and part background.
Formats offering only on-or-off transparency force every edge pixel to one extreme, which is what produces the hard, stair-stepped outline typical of GIF cutouts. It matters most on hair, fur and soft fabric, where much of the subject exists only as partial coverage.
Practical guidance
- Keep a PNG master of any cutout, then export to WebP or AVIF for delivery
- Never round-trip a cutout through JPEG; transparency is discarded permanently
- Check the destination platform accepts your format before converting in bulk
- For flat logos and icons, SVG beats every raster format on both size and sharpness
Frequently asked questions
Which file format supports transparent backgrounds?
PNG, WebP and AVIF all support a full alpha channel, meaning each pixel can be partly transparent. PNG is the safest default because support is universal. GIF supports only binary transparency, and JPEG supports none.
Why did my transparent background turn black or white?
The file was almost certainly saved as JPEG, which has no alpha channel. When transparency is discarded the transparent area is filled with a solid colour, typically black or white. Re-export as PNG or WebP from the original cutout.
Is WebP better than PNG for cutouts?
For web delivery, usually yes. WebP supports the same 8-bit alpha and produces files roughly 25 to 35 percent smaller. PNG remains better when handing a file to someone else, or when it will be re-edited, since lossless PNG survives repeated saves without degrading.
Why can't GIF be used for a good cutout?
GIF transparency is one bit: a pixel is fully visible or fully invisible, with nothing in between. Real subject edges need partial coverage to look smooth, so GIF cutouts show hard, jagged boundaries, and the 256-colour limit degrades photographs further.
What format does Snapcorn output?
Background removal returns PNG, because PNG carries a true alpha channel and is the format most reliably accepted everywhere a cutout is used. Convert to WebP afterwards if you need smaller files for your own site.
Does transparency increase file size?
Yes, modestly. An alpha channel adds a fourth channel of per-pixel data. The larger factor for PNG is lossless compression, which is why a high-resolution PNG cutout can be several times the size of the equivalent JPEG.