Tap Target Checker
Spot buttons and links that are too small or too close together to tap reliably. Free, no account required.
The page is read on our side and nothing is stored.
How this is worked out
The check reads the sizes and padding set for buttons and links in your stylesheets, and looks at the page markup for links sitting directly beside each other. A comfortable target is around 44 by 44 pixels with a little space around it.
Checking whether text is big enough too? Use the Text Size Checker.