Spots on tomato leaves

Thank you for the question. This appears to be septoria leaf spot. You should act right away in order to keep the disease from spreading. Check out the following links for information about the disease and its control.

• https://www.missouribotanicalgarden.org/gardens-gardening/your-garden/help-for-the-home-gardener/adv....
• https://www.canr.msu.edu/uploads/files/septoria%20leaf%20spot.pdf

I hope this is helpful,