E-liquid calculator: how much nicotine shot do you add?

Why an e-liquid calculator exists

E-liquid, also called vape juice or ejuice, is usually sold as a 0mg base — a mix of propylene glycol (PG), vegetable glycerin (VG), and flavoring with no nicotine. To make it vape-ready, you add a nicotine shot: a concentrated bottle of nicotine in the same base. The problem is that "just add some" produces inconsistent strength bottle after bottle, and a too-strong mix is harsh while a too-weak one sends you back to the vape shop a week early.

The math is a one-liner: (target mg × final ml) ÷ shot mg = ml of shot to add. If you want 6mg in a 60ml bottle and your shots are 18mg, that is (6 × 60) ÷ 18 = 20ml. Pour in 20ml of shot, top up with 40ml of base, shake, and you have a consistent 6mg mix. The e-liquid calculator above removes the mental arithmetic and guards against the most common mistake: setting a target higher than your shot strength.

Common mixes at a glance

These are the mixes vapers actually make most often — freebase targets on 18mg shots, nic salt targets on 20mg shots, and shortfill-to-concentrate conversions on 72mg:

Rounded to whole milliliters for practical measuring. Always mix in a bottle sized to your final volume so the headroom accommodates the shot.

What mixing costs versus buying disposables

Home-mixed e-liquid is dramatically cheaper per milliliter than disposable vapes. A 10ml 18mg shot costs $2-4, and a liter of 0mg base runs $15-30 — which works out to roughly $0.20-0.50 per ml of finished juice. A disposable, by comparison, effectively costs $1.50-3.00 per ml of liquid it vaporizes. The vaping cost calculator will turn that per-ml gap into a yearly number, which is usually the difference between a $500/year and a $1,500/year habit.

Freebase vs nic salt shots: which to buy

Nicotine shots come in two kinds, and picking the wrong one is the most common mixing mistake. Freebase shots are the classic 18mg/ml bottles designed for refillable tanks and standard e-liquid. Nic salt shots are usually 20mg/ml and made for low-power pod devices — the salt form stays smooth at high concentration, so a salt mix is meant to be vaped on a pod, not a sub-ohm tank where it would hit too hard.

The strength number on the label is the concentration in mg/ml, and the calculator does not care which kind you choose — it only needs the number. But the target does. Freebase is the right choice for a 3mg or 6mg all-day mix in a tank. Salt is the right choice when your goal is a 20mg or 30mg pod juice that mimics a cigarette hit. If you mix a salt shot to a high strength and put it in a high-power device, you get an intense throat hit and a much faster nicotine spike than you intended.

Shot strengths compared

*One 10ml shot added to a 50ml 0mg shortfill. The rule of thumb: a single shot in a 50ml shortfill makes a 60ml mix at roughly 3mg (18mg shot) or 3.3mg (20mg shot).

PG/VG ratio: how it changes the mix

E-liquid base is a blend of two liquids: propylene glycol (PG) and vegetable glycerin (VG). PG is thin, carries flavor, and provides the throat hit; VG is thick and sweet, produces the visible cloud, and smooths the draw. The ratio printed on the base bottle — 50/50, 70/30, or 80/20 — tells you the balance, with VG listed first on most labels.

The ratio matters because it decides which device the mix works in. A 50/50 base is thin enough to feed the small coils in pod systems and starter kits, which is why most pod shortfills use it. A 70/30 VG base suits sub-ohm tanks, which run hotter and vaporize the thicker liquid well. An 80/20 or max-VG base is for cloud chasing on big rebuildable atomizers — and it will wick poorly, or not at all, in a small pod coil.

When you add a nicotine shot, the shot carries its own base, so the ratio of the finished mix shifts slightly toward the shot's blend. With a 10ml shot in a 60ml mix, that is a small swing — but in a 30ml batch, a VG-heavy shot can visibly thicken the result. Keep your device in mind before you pour: the calculator tells you the volumes, but the base ratio tells you whether the finished juice will actually vape in what you own.

Shortfills, concentrate, and mixing safely

Most mixing today starts from a shortfill: a bottle of 0mg juice that leaves headroom for a nicotine shot. A 50ml shortfill lives in a 60ml bottle, so one 10ml shot fills it exactly; a 100ml shortfill lives in a 120ml bottle and takes two 10ml shots. Because the shot volume is fixed, the finished strength is fixed too — roughly 3mg with one 18mg shot, 3.3mg with a 20mg shot. That is the entire appeal: no measuring, just pour and shake.

If you want real control, you mix from 72mg concentrate — a highly concentrated liquid that must be handled carefully. At 72mg/ml, a few milliliters of concentrate can carry more nicotine than an entire pack of cigarettes, so it deserves the same respect: wear gloves, work in a ventilated area, label every bottle with its strength, and keep everything well out of reach of children and pets. Nicotine is toxic if ingested or absorbed through the skin in quantity, so spill cleanup is not optional.

Whatever route you choose, the payoff is the same as the calculator implies: finished juice at $0.20–$0.50 per ml against $1.50–$3.00 per ml from a disposable. That gap is why so many vapers switch. If the numbers are what finally convince you, the vaping cost calculator turns the per-ml savings into a yearly total.