Fuzzy fonts

Are the images the same file size locally and on the server? If not, there may be some downsizing happening at the server level that's dropping the quality and making things fuzzy.

Is your browser view at 100%? Browsers allow users to set their preferred zoom level. If yours is at more than 100% it will make jpeg text look fuzzy. Hitting Ctrl+0 should bring the zoom level back to 100% if it's set higher. This is a good example of why text should be html on a website. When viewers increase their browser zoom, the text scales up without distorting the edges. 

Personally I rarely, and only for specific use items, ever put text in images online. Jpeg text isn't searchable by visitors, isn't indexable by search engines, gets fuzzy when zoomed, and is totally invisible to screen readers. If the text can be taken out of the image and turned into html, it should be. Your site will be better off in a LOT of ways.

Such is the nature of pixel-based raster images.

Solution:  Use math-based vector graphics instead, see screenshot.  Vectors are scalable to any size that's required without loss in quality.   Vectors are particuarly well-suited for fonts, icons, logos, comics, drawings and other non-photographic web graphics.

Hope that helps.