How much folic acid should I be taking every day?

800 mg. If your pregnant 800 to 1000mg of Folic Acid per day will suffice to help with growth and many metabolic processes for both you and baby. More so having adequate Folic Acid levels before conception (400mg/day) can reduce some birth defects of the heart and nervous system. So it's never to early to start (folate (folic acid) is a water soluble b vitamin so excess is excreted in urine).
0.4 mg. Typically you need 400 micrograms or 0.4mg a day. You get Folic Acid through fruits and vegetables and many foods are already fortified with it. To make sure you get enough you can take any adult multivitamin or two flintstones chewables.
4 mg. If there is a high risk (such as a previous child affected by a neural tube defect, preexisting diabetes, or, on a medication for seizures) the daily dose should be 4 mg.