It isn't really a ratio.

One must make sure they have a full store of B12 and continue getting enough to keep the stores full as small amounts are used. So, in case a person malabsorbs severely, at least 1000 mcg per day is good insurance.

Folate of folic acid is not stored like that (nor is any other nutrient), and it must be eaten or taken regularly for daily use. It would not be outrageous to take 800 mcg folic acid, and some people take much larger doses are taken therapeutically with a doctor's help. The extremely large doses are usually not needed or recommended.

The important thing is to get enough of both, and NEVER to take folic acid when not sure of getting plenty of B12. Of course, one should make sure to get plenty of B12 whether taking folic acid or not. The reason this is mentioned in many places is that when people need B12 but are given instead folic acid, they can be damaged terribly.

One does not need to worry about a ratio of B12 to anything else. One just needs to be sure to get all nutrients and have or develop a strong store of B12.

rose