Email signatures need to be clear and easy to read. Readers need to get pertinent information quickly and easily. Sans serif fonts are best like Arial and Verdana because they are clear and also because most if not all people will have them on their computers.
I would like to add as someone with visual problems that the size should be ‘normal’ or at least 12pt. Most important of all, grey writing and lighter coloured text should not be used. Even people with ‘normal’ eyesight can find these difficult to read.
The amount of time I had to highlight, copy and paste a signature into another document just to read it because someone thought it looked nice to use tiny, light-grey writing on the white background, well, let’s just say i could have been doing something much more useful!
If you want people to be able to read and use your signature, keep it simple, clear and with good contrast. Dark colours against a light background or light colours against a dark background.
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