Almost every quit plan gets better once you know your actual number. Here is how to work it out in about a minute.

The formula

Total nicotine (mg) = volume (ml) × strength (mg/ml)

That is the whole calculation. Percentages are the same thing: 2% = 20mg/ml, 5% = 50mg/ml.

Common devices

Device Volume Strength Total nicotine
UK/EU disposable 2ml 20mg/ml ~40mg
Large disposable (other markets) 10ml 50mg/ml ~500mg
Pod (typical) 2ml 20mg/ml ~40mg
Freebase bottle 10ml 12mg/ml 120mg
Salt bottle 10ml 20mg/ml 200mg

The cigarette comparison, honestly

A cigarette contains roughly 10–14mg of nicotine, but a smoker absorbs only about 1–1.5mg of it. Vaping absorption also falls well short of the total in the liquid, and varies by device, coil, puff length, and whether the liquid is freebase or salt.

So a 40mg disposable is not 40 cigarettes in effect. A reasonable rough statement: a 2ml 20mg/ml disposable delivers nicotine somewhere in the region of a pack of cigarettes for a typical user, and anyone quoting a precise number is over-claiming.

The useful comparison is not to cigarettes at all. It is to yourself last month.

Why salts changed everything

Freebase nicotine above about 12mg/ml is harsh, the throat limits how much you take in. Nicotine salts lower the pH, which removes the harshness and makes 20–50mg/ml comfortably inhalable.

The consequence is a much steeper delivery curve and much higher daily totals than freebase vaping or smoking typically produced. This is the main reason many people find modern vapes far harder to stop than cigarettes.

Work out your daily mg

  1. Estimate your daily liquid use in ml. (Half a 2ml pod = 1ml. A disposable every two days = 1ml/day.)
  2. Multiply by strength.

Examples:

  • One 2ml 20mg/ml pod per day → 40mg/day
  • Half a pod per day → 20mg/day
  • 3ml/day of 12mg/ml freebase → 36mg/day

Using the number

Once you have mg/day, a taper becomes arithmetic instead of guesswork, typically 25% down every 5–7 days, holding a step longer if withdrawal spikes. It also tells you whether nicotine replacement therapy is likely to matter: above roughly 20mg/day, most people do better with patches or gum in week one than without.

Read next: what nicotine does in the brain.