PG/VG Ratios Explained
Vegetable glycerine (VG) and propylene glycol (PG) are the two main ingredients of e-liquids.
Are you confused by vaping terminology and so struggling to select the right e-liquids? It is important to understand the basics of vaping including PG/VG ratios, also known as base liquid ratios.
What is a base liquid ratio?
All e-liquids feature four ingredients - flavourings, nicotine, propylene glycol (PG) and vegetable glycerine (VG). The blend of PG and VG is known as the base liquid and you will find that the ratio of PG to VG varies.
As PG and VG boast different qualities, the ratio of one to the other is varied to create the desired qualities in e-liquids. That ratio is expressed as a percentage or as a number that represents a percentage. For example, e-liquid that is identified as 50PG/50VG features a base that is 50% PG and 50% VG.
The base liquid ratio of most e-liquids is mentioned on product listings online and also on the packaging of the juice.

About Propylene Glycol
Propylene glycol is a synthetic organic compound with the chemical formula C3H8O2. This might sound rather scientific but all you really need to know is that PG is a colourless, odourless and flavourless substance. It is found in many common consumables including pet foods and beauty products. More importantly, research has shown that PG is safe to ingest and to inhale but further research is required.
Volatile compounds which contain PG have been associated with respiratory disorders but it is more than likely that it is the glycol ethers in such compounds which are problematic and not the PG. After all, PG is used in asthma inhalers! You should also be aware that PG can adversely affect the immune systems of cats and so care should be taken when vaping around your feline friends.
Allergies to PG are extremely rare but high levels of PG can result in you experiencing a dry mouth and increased thirst. These symptoms tend to subside as your body acclimatises to the liquid over time. When it comes to vaping, the advantages of PG are clear. It provides an excellent throat hit and delivers intense flavour.
A high ratio of PG is a major boon for recent smokers who are still craving that treasured throat hit.
Vegetable Glycerine
Vegetable glycerine is also found in many products that you use every day including cosmetics, toiletries, medications and food. It is an ingredient which is added to a variety of products to act as a moisturiser and/or sweetener. VG is a benign substance which is derived from vegetable oils.
As with PG, allergic reactions to VG are extremely rare and are most commonly experienced by diabetics. VG is a great choice for vegetarians as the manufacture of PG can involve animal derivatives.
VG delivers a smoother throat hit than PG but more voluminous clouds of vapour and so VG lends itself to sub-ohm (low resistance) vaping.
VG does not carry flavour quite as efficiently as PG and it boasts a naturally sweet taste which can alter the balance of flavour in e-liquids. It is also thicker than PG and that means that it can clog up the heating coils in tanks and pods. Vaping devices which have small coils such as clearomizers, can be particularly susceptible to this problem. On the other hand, sub-ohm tanks are set up to cope well with the viscosity of e-liquids which contain a high ratio of vegetable glycerine.
The Best Of Both Worlds
As propylene glycol and vegetable glycerine both have their advantages and disadvantages, most e-liquids feature a combination of the two. This ensures that the flavour delivery is good, that the heating coils of devices don’t clog up and that generous clouds of vapour are produced.


Which base liquid ratio is right for you?
Hopefully you are now feeling a little more informed about PG and VG. Well, at least you know what those ratios printed on the bottles mean!
E-liquids that feature at least 60% PG are best suited to high resistance coils (1.0 ohm or higher) that are designed for mouth to lung vaping. Those that are at least 60% VG are ideal for low resistance coils (0.4 ohm or lower). E-liquids that are 50% PG and 50% VG are ideal for 0.5ohm to 0.9ohm coils but will perform well in most devices.
