Every product page is a wall of numbers, and most of them are decoration. Five do real predictive work — here is what each actually tells you about living with the device.
1. Puff rating — your calendar
The tank’s machine-measured life. It forecasts how long the device lasts you (at your personal 60–75% conversion) and anchors all value math. A 4,000 rating is a trial or a light-user’s month; 50,000 is a household supply. Full treatment here.
2. mAh — your charging schedule
Battery capacity. Under 600 mAh is a charge-per-evening device; 600–900 mAh buys multi-day stretches; above that you are managing a small power bank. On sealed small formats the number barely matters (the tank dies first); on 30K+ tanks it is the difference between nightly and weekly charging.
3. E-liquid volume (ml) — the honest capacity
When a page lists it, ml is more honest than puffs — liquid volume cannot be inflated by draw conventions. It also enables the only comparison brands cannot game: price per milliliter. Two devices at the same price, one with more ml, is a decision made for you.
4. Coil resistance (Ω) — the draw’s character
Lower ohms run hotter and fuller; higher ohms run cooler and tighter. If you know whether you like a tight cigarette-adjacent draw or an open airy one, this number predicts it before you buy. Sub-ohm on a disposable signals big vapor and big liquid appetite; 1.0Ω and up signals restraint and longevity.
5. Charge current (V/A) — the battery’s lifespan
Almost always ignored, quietly important. Most disposables want plain 5V/1A charging — and a surprising number of battery complaints trace to fast-charge bricks pushing more than the device asked for. Match the cable to the spec and cells live noticeably longer.
The numbers to ignore
Marketing wattage peaks, "dual chip" branding, flavor counts quoted as specs, and any number with a trademark after it. None predict anything you can feel. Read the five that matter on any of our product pages and the spec sheet stops being noise.