How to export gif files in Figma wiithout any white border?

Hi there! As a workaround, please make sure to set the heigh, width, height, and/or X and Y positions are on full integer values, and the numbers have to be closed, both in the image and the frame.

You can have more context here:

Why it happens only exporting as gif file format but not for JSON?

Can you clarify and share an example about what you intend to do with JSON? Are you trying to export images ? (as JSON is not an image format).

As a reminder, you can only export these image formats: PNG, JPG, SVG, PDF. More information in this guide: