DIY e-liquid kit, which one at each stage of learning
Between a ready-made bottle and a recipe built from nothing sits a middle step that is easy to walk straight past. A DIY e-liquid kit is sold as a homemade liquid without the maths, yet the label covers formats that teach very different skills. Pick the wrong one at the wrong moment and you either learn nothing new or get lost in decisions you were not ready for. The question is which kit matches the stage you have reached.
Which DIY e-liquid kit to choose, the short answer by level
The right DIY e-liquid kit depends on what you can already do. If you have only ever added a nic shot to a shortfill, a longfill is the natural next step, because the flavour is measured for you and only the base and nicotine are left to add. Once that step feels familiar, a kit that leaves the flavour choice to you adds a single new decision.
Mixing from an empty bottle, with your own sums, comes last. Each stage adds one variable to master, which is exactly what keeps progress readable.
The UK formats that sit between a shortfill and full DIY
British shelves group several products under the DIY banner. The difference is not size or brand, it is how much of the recipe is left to you, and that is shaped by the law on nicotine containers.
Why nicotine always comes separately
In the UK, any refill container holding nicotine is limited to 10 ml, at no more than 20 mg/ml. Nicotine therefore cannot be supplied inside a large bottle of base, which is why every kit ships its nicotine as separate 10 ml shots that you pour in yourself. Nicotine vaping products are also not for sale to anyone under 18 in the UK.
The longfill, flavour measured, the rest up to you
A longfill is flavour concentrate sold in an oversized bottle. One UK retailer’s guide describes the common format as a 60 ml bottle holding about 20 ml of concentrate, leaving roughly 40 ml for nic shots and unflavoured base. Other ranges put 30 ml of concentrate in a larger bottle, so the label always deserves a look.
The concentrate is never vaped on its own. It is far too strong, and there is not enough liquid for a coil to wick properly.
The complete kit, concentrate, base and shots in one box
Some retailers sell a DIY e-liquid kit that bundles a flavour concentrate, a bottle of PG VG base and nicotine shots. Quantities are matched to a target volume, so the mixer follows the instructions rather than making choices. It is the closest British equivalent to a guided first mix.
First stage, learning the hands-on skills
The complete kit and the longfill both remove the recipe decisions, and that is their real teaching value. They isolate the manual side of home mixing, the part where early mistakes tend to happen.
The skills it builds
Opening and emptying a shot cleanly, pouring without overflowing, capping, shaking, then labelling and dating the bottle. These steps look trivial, yet they cause the spills, the unmarked bottles and the nicotine on fingers. A kit lets you repeat them on a recipe that is known to work.
Gloves belong in that sequence from the very first shot. Nicotine needs careful handling, and the finished bottle is stored somewhere safe, out of reach of anyone under 18 and of pets.
The first lesson in patience
The same guide notes that many longfills are shake-and-vape, that fruit and menthol profiles are often fine straight away, and that dessert and tobacco profiles may improve after a day or two in a cool, dark place. Tasting a mix on day one and again a week later is the clearest way to understand what resting changes, covered in our guide to steeping e-liquid.
Second stage, the DIY e-liquid kit that leaves you the maths
Once the hands-on skills are automatic, the longfill starts teaching arithmetic. You choose how many shots go in, and the base fills whatever space is left.
Strength, worked out on a real bottle
Take a 60 ml longfill with 20 ml of concentrate and 18 mg/ml shots. One 10 ml shot plus 30 ml of base gives 180 mg of nicotine in 60 ml, that is 3 mg/ml. Two shots and 20 ml of base give 6 mg/ml, three shots and 10 ml give 9 mg/ml, and four shots with no base at all reach 12 mg/ml.
With 20 mg/ml shots the same single shot gives 200 mg in 60 ml, or about 3.3 mg/ml. Redoing the sum yourself each time is the habit that later lets you mix any volume, a calculation set out in our guide to nicotine shot dosage.
The ratio becomes your call
A longfill also hands you the PG VG ratio, since you pick the base. A 50/50 suits a tight, mouth-to-lung draw, while a VG-heavy base suits an airy sub-ohm tank. Remember that shots carry their own ratio, so four shots in a 60 ml bottle shift the final blend noticeably.
What a DIY e-liquid kit cannot teach you
A kit has limits, and knowing them stops you stalling. Two skills stay out of reach whatever the format.
Volume planning
A kit fixes the split between concentrate, base and nicotine in advance. Until you have used the 100 per cent rule yourself, you cannot make a different volume or combine two concentrates in proportions of your own choosing.
Reading a concentrate on its own terms
A longfill tells you nothing about the percentage its concentrate would need in a different bottle. Working out a flavour percentage from a manufacturer’s recommendation, and judging whether a base is right for it, are covered in our guide to the PG VG ratio of a DIY base.
Third stage, the signs it is time to leave the kit behind
Moving on to mixing from scratch is not a matter of how many bottles you have made, but of the habits you have built. Three signs show that the kit has done its job.
The first concerns your hands. When opening a shot, pouring, labelling and dating happen without thinking, a complete kit has nothing left to teach them. The second concerns the maths. If you can work out the strength of a longfill with any number of shots, the logic of nicotine strength is in place. The third concerns curiosity. Wanting a different ratio, a different volume or two concentrates in one bottle means stepping outside the frame a kit sets in advance.
At that point the method changes. You no longer follow instructions, you apply the 100 per cent rule yourself and start from an empty bottle.
FAQ
A few questions come up whenever mixers move from a kit to their own recipes. Short answers below.
Can a longfill be used without nicotine?
Yes. Fill the free space with unflavoured base only and the result is a nicotine-free liquid. The flavour strength stays the same, since the concentrate volume does not change.
Is a longfill the same as a shortfill?
No. A shortfill is base and flavour already mixed, waiting only for a shot. A longfill holds concentrate alone, so you choose both the base and the nicotine strength.
Can I start straight away with a longfill?
Yes, if the basic handling already feels familiar, for instance after adding a shot to a shortfill. Choosing the number of shots and the base then comes all at once, which calls for a little more care.
Do shots from a kit differ from shots sold on their own?
No, they are standard 10 ml bottles, capped at 20 mg/ml in the UK. Only their number is matched to the kit.
What if the first mix is disappointing?
Wait first. A mix tasted too early has not finished resting, and the retailer guide quoted above notes that dessert and tobacco profiles may improve after a day or two. Then note what bothers you, so that only one setting changes on the next kit.
A DIY e-liquid kit matched to the stage you are at
A DIY e-liquid kit is not a cut-down version of home mixing, it is a learning tool with clear stages. A complete kit trains the hands, a longfill trains the arithmetic and the ratio, and volume planning comes after.
Choosing a DIY e-liquid kit by level simply means adding one variable at a time. That path leads naturally to a recipe built from an empty bottle, described in our complete method for making your own e-liquid.
Editorial content for adult readers only. Nicotine is an addictive substance, and nicotine vaping products are not for sale to anyone under 18 in the UK. This article is not a buying recommendation.
