This post is for people who are comfortable with very basic math and maybe word problems. No trig, calc, or algebra required. This is also for those who don't like using ejuice calculators or find limitations therein.
When I first started DIY I asked a chemist friend for some magic formula to help me calculate concentrations. His response was: "oh that's easy, it's just additive," but it took me a few days to understand what he meant. In chemistry we need to add multiple solutions with different concentrations, formulas are helpful. The great thing about DIY is there is only one solution (nicotine base), we are just diluting that.
So what the heck am I talking about? I wanted a formula that I could just plug numbers into. If you want that, great, just use a ejuice calculator. I have never used one. I figured this out using logic and a touch of math. If you understand a tiny bit about percentage/decimal/fraction math, you don't need a calculator. It's much easier and quicker for me to do with a regular calculator and paper. Maybe that's just me. If not, then read on.
Some key points for this method are:
I'll use obvious examples so that it is easier to understand mentally, but you can easily do this for any batch after very little practice.
Here's an example:
You have 100 mg/ml nic base, and you want 25mg/ml juice, let's say 10ml of it. This is wicked easy: 2.5ml of 100mg juice and 7.5 ml of 0 mg PG/VG.
2.5 ml of 100mg/ml (2.5 * 100) is 250mg of nicotine. 100 mg/ml is 100mg/1ml, so it looks like this in long form:
2.5ml__100mg
-------- * ------------- = 250 mg
1_______1ml
(Notice the "ml" is crossed out, this happens when we "cross multiply" using fractions.)
Because the 250mg is spread out through the whole batch we divide 250 mg of nicotine by the total finished volume (250mg/10ml) and you get 25mg/ml.
How do I know this? The key is understand your units. The unit mg/ml means "milligrams per milliliter" or "milligrams divided by milliliters". I know some of you are saying, "duh!" and some might be saying: "well that was an easy one...." Some of you might be confused.
If the ratios are not immediately obvious, just guess, check your math, and guess again if you're wrong.
Another example:
We have 36mg/ml nic base, and we want 12mg/ml juice. I think I'll make 30 ml this time. I notice 36 is "3 times 12". So I know I'll need 1 part nic base and 2 parts PG/VG base. That gives us 10 ml of 36 mg/ml base and to add 20 ml of PG/VG base to dilute that to 12mg/ml.
Math check:
36mg/ml * 10 ml is 360mg total nicotine. 360mg total / 30ml total volume is 12 mg/ml concentration (360mg divided by 30 ml)
This should be relatively simple to grasp if you are comfortable using a little bit of math.
For higher flavoring percentage (over 5% maybe):
Okay, so you use Flavor west and need 25% flavor. How do we account for that in the above example? Super easy. We were using 2 components before (nic and PG/VG). Now we need a 3rd. But we already know the correct percentages, we just need to replace some PG/VG base with some flavor. Once you find out how much nic base you need for your batch (10 ml nic base in a 30ml batch in this case) we know the 20ml remaining will consist of PG/VG and flavor. So if we need 25% of the total batch in flavor, multiply 25% by 30 ml. 25% is .25 in decimal form, so the math looks like this:
.25 * 30ml = 7.5ml flavor
Subtract that from our 20ml figure from before and you get 7.5ml flavor and 12.5ml PG/VG base. (math check: 7.5ml + 12.5ml = 20ml YAY!!)
In order to use this method you need to visualize the approximate amounts in your head a little (draw a diagram if it helps), and you need to feel a little comfortable using basic math. I encourage you to use units everywhere possible.
I keep track of recipes in ml and percent where possible so I can just multiply later for different sized batches. This can be done on paper or in digital form.
Does this make any sense to anyone? I'm happy to clarify.
When I first started DIY I asked a chemist friend for some magic formula to help me calculate concentrations. His response was: "oh that's easy, it's just additive," but it took me a few days to understand what he meant. In chemistry we need to add multiple solutions with different concentrations, formulas are helpful. The great thing about DIY is there is only one solution (nicotine base), we are just diluting that.
So what the heck am I talking about? I wanted a formula that I could just plug numbers into. If you want that, great, just use a ejuice calculator. I have never used one. I figured this out using logic and a touch of math. If you understand a tiny bit about percentage/decimal/fraction math, you don't need a calculator. It's much easier and quicker for me to do with a regular calculator and paper. Maybe that's just me. If not, then read on.
Some key points for this method are:
- I mix my PG/VG at a ratio I like prior to mixing a juice. So all I have is Nic base, PG/VG base, and flavor.
- I use mostly super-concentrated flavors and they require only a few percent in the mix which allows you to basically forget this part of the percentage
- If you use a higher percentage of flavor, you can just incorporate the flavor into the PG/VG amount using very basic percentage math which I'll cover
I'll use obvious examples so that it is easier to understand mentally, but you can easily do this for any batch after very little practice.
Here's an example:
You have 100 mg/ml nic base, and you want 25mg/ml juice, let's say 10ml of it. This is wicked easy: 2.5ml of 100mg juice and 7.5 ml of 0 mg PG/VG.
2.5 ml of 100mg/ml (2.5 * 100) is 250mg of nicotine. 100 mg/ml is 100mg/1ml, so it looks like this in long form:
2.5
-------- * ------------- = 250 mg
1_______1
(Notice the "ml" is crossed out, this happens when we "cross multiply" using fractions.)
Because the 250mg is spread out through the whole batch we divide 250 mg of nicotine by the total finished volume (250mg/10ml) and you get 25mg/ml.
How do I know this? The key is understand your units. The unit mg/ml means "milligrams per milliliter" or "milligrams divided by milliliters". I know some of you are saying, "duh!" and some might be saying: "well that was an easy one...." Some of you might be confused.
If the ratios are not immediately obvious, just guess, check your math, and guess again if you're wrong.
Another example:
We have 36mg/ml nic base, and we want 12mg/ml juice. I think I'll make 30 ml this time. I notice 36 is "3 times 12". So I know I'll need 1 part nic base and 2 parts PG/VG base. That gives us 10 ml of 36 mg/ml base and to add 20 ml of PG/VG base to dilute that to 12mg/ml.
Math check:
36mg/ml * 10 ml is 360mg total nicotine. 360mg total / 30ml total volume is 12 mg/ml concentration (360mg divided by 30 ml)
This should be relatively simple to grasp if you are comfortable using a little bit of math.
For higher flavoring percentage (over 5% maybe):
Okay, so you use Flavor west and need 25% flavor. How do we account for that in the above example? Super easy. We were using 2 components before (nic and PG/VG). Now we need a 3rd. But we already know the correct percentages, we just need to replace some PG/VG base with some flavor. Once you find out how much nic base you need for your batch (10 ml nic base in a 30ml batch in this case) we know the 20ml remaining will consist of PG/VG and flavor. So if we need 25% of the total batch in flavor, multiply 25% by 30 ml. 25% is .25 in decimal form, so the math looks like this:
.25 * 30ml = 7.5ml flavor
Subtract that from our 20ml figure from before and you get 7.5ml flavor and 12.5ml PG/VG base. (math check: 7.5ml + 12.5ml = 20ml YAY!!)
In order to use this method you need to visualize the approximate amounts in your head a little (draw a diagram if it helps), and you need to feel a little comfortable using basic math. I encourage you to use units everywhere possible.
I keep track of recipes in ml and percent where possible so I can just multiply later for different sized batches. This can be done on paper or in digital form.
Does this make any sense to anyone? I'm happy to clarify.
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