A “hit” is counted every time a webthumb is served to someone using your API key. You can reduce the number of hits by caching webthumbs on your site and serving them from there.
Image size controls the width (in pixels) of the image. The height depends on the requested aspect ratio, which is 4:3 by default. This table shows the image sizes based on the default aspect ratio (view a demo):
|f||full size||Up to 1920×1440|
A “label” is a short line of text that is printed over top of the image in the lower left corner. For the free plan, this is simply “webthumbs.ca”. For the standard and premium plans there is no label. On the enterprise plan you can customize it or remove it.