Growth

This has grown on my dogs paw over the last few months any idea what it is . 

Hi!  I think that the subject of this picture is a thickening of the inside skin between two adjacent toes of a dog.   Presumably there is a further toe (medial) out of view of the camera.  What else can you tell us?  Is your dog licking it?  Is there a lump or foreign body present?

Sometimes paws look a bit like this when, for example, a dog treads on a thorn or a grass seed and it slips into the skin (grass seeds are sharp).   However allergies can also have this kind of effect, especially between the toes as combined with the hotness / wetness there.   In general, a grass seed or foreign body would be just in one place; an allergy would affect all of the skin webs.  There are other causes too and your vet will be able to look at this with real resolution (ie not on a phone).  Skin diseases get ten times worse over a short space of time with licking so we would always advise a buster collar etc to stop the licking.  However, if you can imagine something really itching and you wanting to get at it for a long time, simply applying a buster collar to prevent that must be extremely uncomfortable.  For this reason pain relief and treatment are needed:- ask a vet to look at it as soon as is feasible. Best of luck.

(Pain relief needs to be prescribed by a vet - please never give this yourself without consulting them).