White is held here. One tap releases the other three swatches.
Why a form asks for this
Upload forms are built around one checker, and the checker is old. It wants a JPG because JPG is what every library on the server can open, and it wants the empty part of the frame to be white because a scanned page is white and a signature on white is legible when it is printed. A PNG with transparency arriving at that checker is handled by whatever the library does by default, which is frequently black.
So the safe move is to make the decision yourself, here, where you can see it, rather than leave it to code on the other end that will not tell you what it did.
The order to do this in
- 1Open the PNG here and check the picture on white. The empty parts of the frame should read as page, not as a box.
- 2If the form also caps the file in kilobytes, do the format first and the size after. Changing a format changes the size; changing a size does not change the format.
- 3Save the JPG and open it before you upload it. A preview is drawn from the same arithmetic, and it is still worth thirty seconds to look at the file itself.
When white is wrong
- The artwork is white, or nearly. It disappears. Use a colour that is not the artwork.
- The destination is tinted. The JPG will show as a bright rectangle on the page it sits on.
- The artwork was cut out of something dark. Its part-covered pixels carry that dark colour, and on white they show as a rim. The other routes have the swatch that reads the colour out of the edge for you.
- The transparency is the point. A logo meant to go on other people's pages should stay a PNG and be given a matte only when it is placed.
Questions about white
The form says white background. Is this what it means?
Usually yes, and it is worth checking what the picture is. A passport or exam photograph wants the wall behind a person to be white, which is a photography problem. A signature or a document scan wants the empty part of the frame to be white, which is this. Pure white here means the value 255 in all three channels, with nothing behind it.
Why is white not always the right answer?
Because the destination may not be white. A logo flattened onto pure white and then placed on a tinted page shows a visible rectangle where the JPG ends. If the page it lands on has a colour, the matte should be that colour, and the picker on the other routes takes any value you can type.
Does white ruin the edges of white text?
White text on a transparent background disappears into a white matte, because that is what flattening onto white does to it. The picture is not damaged, it is gone. This is one of the cases where the only sensible answers are a different matte or keeping the PNG.
Is the white pure, or nearly white?
Pure. The swatch reads a token and the token is 255, 255, 255. JPEG quantisation can move an isolated pixel by a step or two in a busy area, but a wide flat field of white stays white, because flat is the thing that format handles best.
