Seeds

Is there a certain size for seeds or do the come in different sizes. I received some small seeds that still look good, but before that I had only seen big ones. Is this normal? Is it ok?

Size doesn't matter, it varies from every strain Sativas tend to be smaller though.

all the seeds ive had vary in size i mainly go on the colour if its a brown with blackish spots they are normally good paler almost white ones seem to fail germing