Change it from 60/40 to 77/23 and it'll calculate 
that will be painful on the throat lolChange it from 60/40 to 77/23 and it'll calculate
I see!!About the strongest mix you can make with with the single flavor 60/40 is 18mg nic. The nic level of your base is what is limiting this. Reduce your target strength in the calculator step by step and watch the results each increment and I think it will start to become clearer to you.
it also means this calculator is inaccurate because it does not tell you the resulting PG / VG mix
It is sill possible if you are talking about 50%PG/50%VG depending on the strength of the nic as you are diluting it with other things. Again the versatility is determined by the strength of the base more than anything else.also does that mean if I got 50% PG as base I would not even be able to create 50% 50% mix juice? as it wouldnt work?
Also keep in mind that if you are using higher strength base you need to have both plain VG and plain PG to dilute it to get the level you are shooting for.
I thought it I purchased 52mg PG based nicotine then it would automatically be diluted when I add plain VG and flavoring, please clarify?
Your flavor strength is going to be subjective so even though you run the calculator for 5% flavor, once you mix it you may find that you need 10% or even 15% flavor to get the taste you want. This is going to throw all you other levels off and you will need to re-calculate again for the new flavor level...