Everyone enjoys bluelectronic cigarettes differently. So the number of puffs you get from cartridges varies from person to person. Just like you might finish a cigarette quicker than your friend because you take longer puffs. The same is true for blu.
We use a built-for-purpose 'puff tester' machine to test the flavour and vapour consistency of our cartridge refills. Under these laboratory conditions, we found each cartridge lasts an average 300 puffs (with four second breaks between puffs). That's approx. 30 cigarettes worth.