Definitely a common frog (Rana temporaria), and looks like a female full of spawn on her way to a nearby breeding pond. You can tell it's a common frog (as opposed to a common toad) by the large, dark 'bandit mask' type patch behind the eye on the side of its head that covers the eardrum (the circular shape you can see within the dark patch). Colour can vary a lot in common frogs, with brown, grey and olive green often being prominent, but extremes of colour can include orange, red, yellow and even albino. Individual frogs can also slowly change colour in response to temperature and light.
The skin of frogs is fairly smooth and they usually look moist and shiny when you see them on land. The common toad has quite rough and granular (warty) skin, and often looks fairly dry when on land. Adult common toads are usually a bit smaller than an adult common frog, although their size ranges do overlap, so you can't go by size alone. Hope this is useful.