# PG VG: reading the ratio on an e-liquid > PG VG: what the two acronyms stand for, how to read a 50/50 or 70/30 ratio, why UK bottles often list VG first, and what shortfills change. Two acronyms of two letters, a slash, two numbers. The **PG VG** line appears on every bottle sold in Britain and no label has ever explained what it covers. The vaper works out that a 50/50 does not behave like a 70/30, without knowing which of the two numbers commands what, and which way round the shop meant them. It is the single most structuring piece of information on an e-liquid listing. ## What PG and VG stand for PG is short for propylene glycol, VG for vegetable glycerine, also called glycerol. They are the two base components of an e-liquid, blended in a stated proportion written as a ratio, 50/50 or 70/30 being the two most common on UK shelves. Both carry a European food additive number, E1520 for propylene glycol and E422 for glycerine. Together they account for nearly all the volume in the bottle, the rest being flavourings and, where present, nicotine. ## How a PG VG ratio is written, and the British trap The notation looks simple right up to the moment two bottles carry mirrored numbers for identical behaviour. One point of convention explains that apparent contradiction, and it matters more in Britain than almost anywhere else. There is no universal rule about which figure comes first. A large part of the UK market writes the glycerine figure first, listing a thick sub-ohm liquid as 70/30 VG PG, while continental listings for the very same juice put propylene glycol first and call it 30/70. Both descriptions are accurate, and both appear in British search results for the same product. The practical answer is to read the letters, not the numbers. British retailers almost always spell out which side is which somewhere on the page, and the expanded wording is printed in small type on the back of the bottle. Where a listing gives only bare figures, the safest reading is the coil it recommends: anything paired with a sub-ohm coil is glycerine dominant, whatever order the numbers appear in. That single habit removes most of the ordering mistakes attached to this **PG VG** line, and it costs a few seconds per purchase. ## What each component brings The two liquids do not play the same role in the blend. Their opposing physical properties explain most of what a vaper notices moving from one bottle to another, and therefore why the proportion is worth dosing at all. Propylene glycol is thin and barely viscous. It travels easily through wicking ports, including narrow ones, and it carries the flavour molecules. It also transmits the sensation at the back of the throat that British vapers call throat hit, which is the property people most often notice when a ratio changes. A high PG figure gives a liquid that soaks in quickly, gets along with higher resistance coils and renders flavour crisply. The trade-off is a noticeably more discreet cloud of vapour. Vegetable glycerine is much thicker and faintly sweet. It produces a far greater volume of vapour for the same quantity, and its viscosity slows down how fast the wick refills. A high VG figure therefore demands wide wicking ports and a low resistance coil, otherwise the cotton does not resaturate between puffs and you get a dry hit. ## Why 100 per cent VG barely exists Some ranges advertise a max VG or full VG line, which implies no propylene glycol at all. The formulation reality is a little different, and the detail belongs in a glossary. Flavour concentrates are themselves diluted, most often in propylene glycol acting as a solvent. A liquid sold as max VG therefore carries a residual fraction of PG brought in by its flavourings, typically a few per cent. Manufacturers who want to avoid that use concentrates diluted in another solvent, which remains a minority practice. The wording should be read as an indication of dominance rather than as an exact composition. ## Matching a PG VG ratio to the hardware This is where the acronym stops being abstract. The ratio decides directly which sort of device a liquid works on, and a mismatch is paid for immediately in flavour and wicking. A thin, PG dominant liquid suits tight draw devices with higher resistance coils, which in Britain means most MTL pod kits and clearomisers. A thick, glycerine dominant liquid is aimed at higher power builds with wide airflow, the natural territory of rebuildables, starting with [the RDA and its open deck](/uk/rda-vape/). A 50/50 blend is the all rounder, and it is the format used for nic salts, whose fluidity suits small pod devices. Multi mode kits such as the [Vaporesso Luxe XR Max 2](/uk/vaporesso-luxe-xr-max-2/) are sold with two pods precisely because a single bottle cannot serve both draw styles well. ## Shortfills, nic shots and the UK ratio arithmetic British vaping vocabulary adds a layer here that does not exist everywhere, and it changes the final ratio in the bottle. Nicotine containing e-liquid is capped at 10 ml per bottle and 20 mg/ml of strength, and refillable tanks and pods are capped at 2 ml. Shortfills exist to work within those rules. A shortfill is a larger bottle sold at zero nicotine, therefore outside the 10 ml cap, deliberately underfilled to leave headroom. A nic shot, a 10 ml unit of nicotine base, is added into that headroom before use. The ratio arithmetic follows. Nic shots are usually sold as 50/50 or as pure PG, so adding one to a 70/30 shortfill pulls the finished blend a little towards propylene glycol. Most shortfills are formulated with that shift already anticipated, which is why the stated **PG VG** figure on the bottle describes the blend after the shot goes in rather than before. DIY base bottles use the same acronyms with a different meaning again. A base sold as 50/50 contains the two components alone, with no flavouring and no nicotine, ready to be built up. ## Reading a British e-liquid label The ratio is only one of the mandatory items on a bottle. Placing them relative to one another avoids mistaking a regulatory line for a marketing one. Four blocks share a UK label. The first gives composition, including the ratio and the nicotine strength in milligrams per millilitre. The second carries the mandatory warnings and hazard pictograms, including the notice that the product contains nicotine and is not for under-18s. The third identifies the manufacturer and the batch number, which is what a recall works from. The fourth holds the trade name and the flavour description, the only genuinely free space on the label. ## Frequently asked questions ### Does the ratio change how long a coil lasts? Heavily glycerine based and sweetened liquids gunk up wicks faster. The ratio plays an indirect part, through viscosity and through the flavourings that come with it. ### Can two bottles of different ratios be mixed? Yes, the mix gives an intermediate ratio in proportion to the volumes. The two flavour profiles combine with no guarantee of a pleasant result. ### What does a PG VG 0 entry on a listing mean? It usually indicates a pure flavour concentrate, meant to be diluted. That type of product is never vaped as it comes. ### Is vegetable glycerine of animal origin? The word vegetable refers to the source of the glycerol, extracted from plant oils. Manufacturer datasheets state the exact origin. ### Why does one e-liquid exist in several ratios? Because the range targets several kinds of hardware. The maker declines the same flavour recipe in a thin version and a thick one. ## Reading a ratio in one sentence A **PG VG** ratio states the proportion of the two base components of an e-liquid, propylene glycol and vegetable glycerine, and that proportion governs fluidity, flavour rendering and vapour volume. Nothing else on the bottle tells you as much about how it will behave. The useful reflex in Britain is to check which way round the figures are written before ordering, then match the ratio to the hardware in hand. The neighbouring entries in the [acronyms section](/uk/category/acronyms/) detail that hardware, from the rebuildable deck to the cell that powers it, and they read best alongside this **PG VG** entry rather than in isolation. 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.