Longfill, shortfill or flavour concentrate: what's what?

In short: a longfill is flavour in an oversized bottle, which you top up yourself with base and nicotine shots. A shortfill is a ready-mixed, nicotine-free e-liquid in a bottle that is not quite full, so all you add is a shot. A flavour concentrate is the pure taste, which you dose freely into your base. All three lead to the same place: a liquid with your flavour and your nicotine strength. What changes is how much of the mixing you do yourself.

An honest note first: we do not sell longfills in the German sense of the word. What we offer comes to the same thing and often leaves you more freedom: 30 ml concentrates that you turn into a liquid with a base and a shot, and 50 ml e-liquids at 0 mg that work exactly like a shortfill. Here is how to use both.

What exactly is a longfill?

With a longfill, a small amount of flavour is sold in a much bigger bottle, for example 10 ml of flavour in a 60 ml bottle, or 20 ml in a 120 ml bottle. You fill the rest with unflavoured base and, if you want nicotine, with nicotine shots. Shake, let it steep, done. The manufacturer has already set the ratio: the bottle size tells you how much base goes in.

A longfill flavour is therefore just a flavour with the instructions built in. The upside: no maths, no graduated bottle needed. The downside: you are tied to one bottle size and one percentage, and the amount per purchase is small.

Shortfill: a ready liquid, just without nicotine

A shortfill is an e-liquid that is already mixed, nicotine-free, and filled into a bottle that is not full to the top. The free space is there for your nicotine shot. The classic format: 50 ml of liquid in a bottle that still takes a 10 ml shot.

That is exactly how our French 50 ml e-liquids are made: they are sold at 0 mg and overdosed in flavour, so the taste stays full once the shot is in. With one Unicorn Boost at 20 mg/ml you get 60 ml at about 3.3 mg/ml.

Flavour concentrate: the free-form option

A flavour concentrate is the pure taste, highly concentrated, in a bottle that holds nothing but the flavour. You dose it as a percentage of the final volume into an unflavoured base, usually between 10 and 20 %. The exact figure and the steeping time depend on each flavour and are given on its product page.

Technically it is the same thing as in a longfill, without the set bottle. You choose the volume, the dose and the nicotine strength. And you get more: 30 ml of concentrate makes about 200 ml of finished liquid at 15 %, and 150 ml at 20 %.

Longfill, shortfill, concentrate, ready-to-vape: compared

How to do it with our products

Route 1: like a shortfill (50 ml + 1 shot)

Open the 50 ml bottle, add one 10 ml Unicorn Boost, close it, shake well. Result: 60 ml at about 3.3 mg/ml. Three examples:

• Tatin d'Octobre Unicorn 2026: a homemade tarte tatin, soft apples candied in butter caramel on a golden, crisp pastry.
• Figue de Septembre Unicorn 2026: a ripe, fleshy fig coated in mellow honey and lifted by crunchy walnuts.
• Tobacco Mix Maousse Lab: blond tobacco with light dark-tobacco notes.

Need more volume? In our large formats the maths is the same: 2 shots per 100 ml, 4 per 200 ml, about 3.3 mg/ml each time.

Route 2: like a longfill (concentrate + base + shot)

This way you build your own longfill, in the size you want. You need a base (Unicorn Base 500 ml or 1 litre, unflavoured, nicotine-free, made in France), Unicorn Boost shots and a flavour. A graduated bottle is all you need to mix. Three recipes at 15 % flavour:

• 120 ml at about 3.3 mg/ml: 2 shots (20 ml) + 18 ml flavour + 82 ml base.
• 60 ml at about 3.3 mg/ml: 1 shot (10 ml) + 9 ml flavour + 41 ml base.
• 100 ml nicotine-free: 15 ml flavour + 85 ml base.

Flavours from our Flavours & Concentrates range that are dosed around these values:

• Heisenberg Vampire Vape 30 ml: notes of many red berries and a distinctive freshness. 10 to 20 %, steep two to three days.
• Red Astaire T-Juice 30 ml: a fresh blend of black grape, eucalyptus, aniseed and menthol. 15 to 20 %, three to seven days.
• Lemon Tart Dinner Lady 30 ml: a lemon meringue pie. 15 to 20 %, one to two weeks.
• Pie Vapland 30 ml: an old-fashioned pie filled with pecan. 15 to 20 %, three weeks.

Careful, not every flavour is dosed at 15 %: Ragnarok Sweet Ultimate (strawberries, raspberries, blackcurrants and blueberries with a blast of super-powerful freshness) is dosed at only 5 to 10 %. Always check the product page.

Rather not count base and shots separately? The Mix&Go PURE Base Pack combines an unflavoured base and the nicotine shots. According to the manufacturer, the formulation by Pure laboratories greatly shortens steeping time: your mixes are ready within a few hours.

Same flavour, two formats: La Chose

La Chose by Le French Liquide comes in both forms in our shop: as a 50 ml e-liquid (the shortfill principle) and as a 30 ml concentrate. Salted butter caramel, roasted hazelnut, coffee, then notes of vanilla and pecan. The La Chose concentrate is a limited edition for the liquid's 10th anniversary, made in a single batch: 15 to 20 %, one week of steeping. La Chose 50 ml is ready with a single shot.

Which route suits you?

• You do not want to calculate anything: one 50 ml + one shot. Ready in a minute.
• You liked longfills for their simplicity: route 2 in 60 or 120 ml with the recipes above. For another volume, the DIY calculator does the maths.
• You vape a lot: one 30 ml concentrate and a 1 litre base make far more liquid than a typical longfill.
• You are new to DIY: start with our beginner's guide, then the step-by-step method and the starter kit checklist.

Frequently asked questions

What is a longfill?

A flavour concentrate sold in a bottle bigger than its contents. You top it up with unflavoured base and, if needed, nicotine shots. The bottle size sets the flavour ratio.

Longfill or shortfill?

A shortfill takes the least effort: one shot, shake, done. A longfill or a concentrate takes a little more mixing but gives you more freedom on volume and nicotine strength. With us: 50 ml liquids for simplicity, 30 ml concentrates for freedom.

How much flavour per 100 ml?

It depends on the flavour, usually 10 to 20 %, so 10 to 20 ml per 100 ml of finished liquid. Nicotine-free example at 15 %: 15 ml flavour + 85 ml base. Some flavours are dosed lower, such as Ragnarok Sweet Ultimate (5 to 10 %). The exact figure is on each product page.

Do you sell longfills?

No, not in the German sense of the term. You get the same result with a 30 ml concentrate, a base and a Unicorn Boost, or more simply with a 50 ml e-liquid and one shot.

How long should I let it steep?

For a mix made with a concentrate, it depends on the flavour: from two to three days for Heisenberg to three weeks for Pie Vapland, according to their product pages. With the Mix&Go PURE Base Pack, the manufacturer states a few hours.

Are flavour and concentrate the same thing?

In everyday DIY language, yes: both words mean the pure taste you dilute into a base. On our product pages we use "concentrate".