My nails have light purple/grey near cuticle&entire big toenails purple/grey. no pain, no change of shoes, no excessive standing, no diabetes.

Nail problem: Could be possible fungal infection. Without seeing it, it's hard to tell. A picture may help or seeing a doc locally would be best.

Many possibilities: This could be due to trauma or due to infections or a soft tissue tumor. Have it evaluated by a professional to get the appropriate treatment. By leaving it alone it may get worse.