This is a tough question to answer because how long a jar of Shine will last totally depends on how much you use with each brushing.
That said, here are some ideas to help.
When we first created Shine, we would sprinkle Shine onto a moistened toothbrush using our small wooden spoon that we’ve included in each jar of Shine. Whatever clung to the moistened bristles is what we would use. Then we calculated the weight of the amount of Shine it took to get that amount on our brush.
That amount of Shine was .25 grams and there are 60 grams of Shine in a jar. So, if you use the ‘sprinkle over your brush’ technique to apply Shine to your brush, there will be around 240 uses. If one person brushes twice daily, we can approximate 120 days or 4 months.
However, we have since adjusted how we apply Shine to our brush at home. Now we take a moderate scoop and put it in the palm of our hand or a small dish. In this way, we can dip our brush repeatedly into a set amount of Shine without risking getting any water/saliva into the whole jar. (You see, Shine really likes moisture. So, if any moisture gets into the jar, the powder will begin to clump and get tougher to use.)
Now with our ‘put a scoop in the dish’ technique to apply Shine to our brush (and thereby get Shine throughout the mouth much more effectively), we go through more Shine.
I get probably 60 brushings from a jar using a big scoop each time.