I'm creating an email in Mailchimp and trying to insert icons as images. Mailchimp doesn't support svg files, so I converted them to pngs in illustrator (exported for web). They're still appearing as fuzzy on desktop and mobile, no matter what size I export them as. Any suggestions for maintaining the quality of these icons?
It depends on the resolution you export. SVGs will never be fuzzy due to it being vector, PNG will be fuzzy if the pixel desnity is not high enough.
Rule of thumb, depending on how you are saving it, you should scale the svg to the size you want or define it as the size you want if you are exporting as asset in illustrator.
PNGs exported from Illustrator shouldn't be fuzzy.
Perhaps you are not viewing the images at 100%? Don't zoom in on raster images, or they will look fuzzy.
If you have a high resolution display, some computer systems scale the images up. Check your system scaling is off.