Best image format for online forms and email attachments

Online forms often reject files for one of two reasons: the format is not accepted, or the file is too large. The right fix depends on the file.

• Try JPG when you need broad compatibility.
• Try PNG when sharp text or graphic detail matters.
• Resize the image when the dimensions are too large or the file is too heavy.
• Convert HEIC to JPG when the source image came from an iPhone.

For email attachments, JPG is often the easiest choice because it stays widely supported and usually keeps file size lower than PNG.