Minimum font sizes

Notice: Updated version available

Regular readers would know that I advocate against hard-to-read text - either due to low contrast or because the font sizes are too small. I call this phenomenon Positive Fantasy Syndrome.

Tahoma 11px (8pt) used in XP
The minimum size for Windows.

But, here is a secret for you - Both Microsoft and Apple have tested extensively how small you can write text on a screen. They use this information to know how small they can make menus, status bars and dialogs - and still have a readable system.

Web-designers should use Apple's and Microsoft's font-size guidelines as the minimum size you can make text on a website.

Minimum system font sizes:

Microsoft: 11px Tahoma
Apple: 11px Lucida Grande Regular

Notice: The Microsoft XP Visual Guidelines state that you can use 8pt Tahoma, but 8pt Tahoma is the same size as 11px Tahoma in your browser. Microsoft has inconsistent font-sizes between system and browser.

Tip:

Make you body font-size 70% (the exact same as 11px Lucida/Tahoma), then you can use em's to size everything else - 1em is then the minimum size you can use. It is a quick and easy way to ensure that you never make your font-sizes too small to read.