# DIY e-liquid kit: what is really in the box? > What a DIY e-liquid kit actually contains, how to work out its cost per bottle, and the mistakes that spoil a first attempt at home mixing. A ready to vape bottle empties in a few days and the spending follows the same rhythm. On a shop shelf, one carton gathers base, flavour and nicotine under a single name. What remains is knowing what a **DIY e-liquid kit** holds exactly, and whether the promise of saving money survives the box being opened. ## What a DIY e-liquid kit contains, concretely A **DIY e-liquid kit** brings together three things sold as one: a neutral base in a large format, one or more flavour concentrates, and the nicotine shots the target strength calls for. The whole thing is calibrated for a defined final volume, often somewhere around half a litre. The value of a kit lies in that calibration. The seller has already worked out how much concentrate the supplied base volume needs, which spares you buying three separate references and guessing the proportions. British kits also tend to include the small hardware: empty graduated bottles, a syringe or two, and a pair of gloves. Those items are not marketing padding. They are exactly what a beginner discovers is missing halfway through a first batch, and has to buy separately afterwards. Some suppliers sell the base already blended at a fixed ratio, others supply propylene glycol and vegetable glycerine in separate bottles and leave the ratio to you. The second arrangement is more flexible and slightly more work, and it makes the [base liquid](/uk/base-liquid/) choice yours rather than the seller's. ## The calculation that really compares the cost per bottle This is the central argument for mixing at home, and it deserves checking rather than assuming. A **DIY e-liquid kit** does come out materially cheaper per millilitre than a ready to vape bottle, on condition that the sum is honest. An honest sum adds three lines: the cost of the base pro rata to the volume used, the cost of the concentrate at the percentage chosen, and the cost of the nicotine shot where the target strength requires one. Divide that total by the final volume you obtain. Here is the part people forget: the most expensive line in a kit is almost always the flavour concentrate, not the base. A good concentrate weighs more heavily in the total than a litre of neutral PG and VG, particularly on dessert profiles that call for a high percentage. Once the three lines are added, the bottle you end up with typically costs around half as much per millilitre as an equivalent ready made e-liquid of comparable size. The gap widens further on larger volumes, since a litre of base costs proportionally less than a half litre. That gap assumes two things: that you do not ruin the batch, and that you do not leave an opened bottle evaporating in a cupboard. The maths behind a kit loses all meaning if half the carton goes unused. ## The minimum equipment to start without overspending A complete kit already includes the essentials, but two or three additions change the precision of the result without weighing much on the outlay. Base, concentrate, shot where needed and a graduated bottle are enough to prepare a simple first recipe. No other purchase is strictly necessary for a fruit or menthol blend, which are the two profiles most likely to survive a beginner's approximations. Precision scales refine dosing beyond what the markings on a bottle allow, which matters for strong concentrates used below three percent. Scales are the one purchase that genuinely goes beyond the contents of a standard kit. Extra empty bottles in 10 or 30 ml sizes stop you keeping a whole litre open day to day. Decanting limits exposure to air and light, the two factors that age a preparation fastest. ## The beginner mistakes that spoil a DIY e-liquid kit Most failed batches do not come from a bad recipe but from rushed handling upstream. Three errors turn up almost systematically on a first attempt. Dosing the concentrate by eye is the first. Pouring without respecting the percentage on the product sheet produces either a flat liquid or a burnt taste from the first puffs on a saturated coil. The graduated bottle in the box exists precisely to remove that guesswork. Skipping the steeping time is the second. A freshly mixed flavour has not yet married with the base. Complex dessert profiles want several days of rest before they show their real character, against a few hours for a simple fruit. Handling nicotine without precautions is the third. The nicotine shot in a kit is handled with gloves, well out of reach of children and pets, on a surface that wipes clean in case of a splash. The bottle then goes back into storage away from direct light, like the rest of the preparation. The exact quantity of nicotine to add is calculated from the final volume and the strength of the shot, never from a ready made figure found elsewhere. Under the Tobacco and Related Products Regulations 2016, shots are capped at 20 mg/ml in 10 ml bottles and tanks at 2 ml, and nothing may be sold to anyone under 18. Our guide to the [nicotine salt shot](/uk/nicotine-salt-shot/) sets out the arithmetic in full. ## Not oversizing your first DIY e-liquid kit The costliest mistake does not show itself straight away. It appears when an opened litre of base yellows at the back of a cupboard, having never been used in time. A first kit is better kept modest in volume, even where the price per litre looks more attractive on a large format. Validating a flavour profile on a test bottle beats committing to a capacity that assumes weeks of steady consumption. The most reliable reference point is your genuine monthly usage, not the saving printed on the packaging. An oversized kit cancels the very gap it was meant to create, in wasted material rather than in net gain. The second sizing question is the ratio. A kit built around a 50/50 base suits pods and mouth to lung tanks, while a high glycerine kit belongs with sub ohm coils. Reading the numbers in the right order is a habit worth acquiring before ordering, and our note on the [70/30 ratio](/uk/70-30-ratio/) explains why the same figure describes two opposite products. ## Frequently asked questions ### Is a kit suitable for someone new to vaping? Yes, provided you choose a simple flavour profile for the first attempt. Fruits and menthols forgive small dosing imprecisions far better than complex desserts do. ### How long does an opened kit last? Unflavoured base keeps for months away from light. Once the final blend is made, its life depends mostly on the concentrate, since some profiles oxidise faster than others. ### Do I need scales to use a kit? No, the markings on the supplied bottle are enough for a simple recipe. Scales become useful beyond two or three ingredients, or for very low concentrate percentages where precision shows. ### Can I adjust the PG/VG ratio of a kit? The supplied base is usually a general purpose compromise that suits most hardware. You can still top up with a base of another ratio to tune the blend to the coil you actually use. ### What should I do with a part used kit? Close each bottle carefully and store it upright, away from light and heat, out of reach of children and pets. A partly used kit keeps perfectly well for a later batch as long as the containers stay properly sealed. ## DIY e-liquid kit: do the sums before buying, not after A kit is only worth having if its contents match a real pattern of use, calculated rather than assumed. The trio of base, concentrate and shot replaces neither the cost per bottle check nor a sensible view of quantities. The most economical **DIY e-liquid kit** remains the one sized on a month of vaping, not on the headline price per litre. Once that logic is in place, each new kit takes a couple of minutes to choose, with no need to start the calculation again from scratch. Editorial content for adult readers only. Vaping products usually contain nicotine, a substance that causes addiction. Not for sale to under-18s in the United Kingdom. This article is not a buying recommendation.