Paneer is a milk product,  Tofu is a soy product. 

Paneer can easily be prepared at home, while making tofu is a bit difficult task as it is made by coagulating soy milk and pressing the resultant curds into soft white blocks.

Tofu is mainly used by vegans or someone who is looking to lose weight. Paneer when made with full fat dairy, is very soft due to the high fat content, 

Soft tofu may have the lowest fat content, it is easy to digest and more likely to contain more nutrients that are absorbed by the body.

Which one is healthier?

According to Dietitian Ashu Gupta 

Tofu is a much healthier option instead of paneer. 

100 grams of tofu has about 60-65 calories, while 100 grams of paneer may have about 260 calories. Iron content in tofu is more than that of paneer. Both have sufficient amount of protein content. She recommend tofu for those who wish to lose weight

 Iron content in tofu is also more than that of paneer. 

Those who are on a diet should include more tofu in their plan. 

WHICH IS HEALTHIER?

Tofu is Rich in essential amino acids, vitamin B1 and low in fats, tofu qualifies as the healthier option among both.

* Tofu is good for people who have cardiovascular problems, are diabetic or are on a weight loss plan.

* Tofu has '0' cholesterol in it while paneer has up to 90mg of cholesterol in 100 grams of paneer.

* Tofu has vitamin B1 and essential amino acids but paneer does not have both.

* Those are allergic to soy can go for paneer and people allergic to milk can go for tofu. 

*  If you are a vegan tofu is one of the best vegan sources of protein.

*100 grams of paneer has 18.3 grams of protein and the same quantity of tofu has only 6.9 grams of protein.  due to the high amount of fat paneer has, tofu is still a better choice for people on a weight loss plan.* Making a choice between tofu and paneer is not an easy  task. But yes, if someone is on a weight loss plan then definitely tofu is the best  answer for you.

Note : It is best to consult a dietitian or your general physician and get a modified diet plan that suits your body and lifestyle.