Evolution of E-Liquid | Going from High PG to High VG

Jun 22, 2022Updated Sep 17, 20265 min readVape School

Vape juice has changed almost as fast as the devices that use it. Within a few years, most of the bottles on shop shelves went from thin, high-PG blends to thick, high-VG juice, and the reason comes down to hardware.

Here is how the balance of propylene glycol (PG) and vegetable glycerin (VG) evolved, what each blend feels like, and how to choose the right one for the device you use today.

A quick refresher on PG and VG

Most vape juice is built on two base liquids. PG is thin, carries flavor well and gives a stronger throat hit. VG is thick and slightly sweet, and it makes denser vapor with a smoother feel. The ratio between them shapes how a juice hits, how much vapor it produces and which devices it suits. For the full explainer, read What Are PG and VG?

Labels list the ratio as PG/VG or VG/PG, depending on the brand, so check which number comes first. The ratios below are all written PG/VG.

How e-liquid evolved

The cartomizer era: high-PG juice

Early vaping devices ran at low power, and many used cartomizers: cartridges with a small coil surrounded by filler material that held the juice. Those tiny coils had very little wicking material, so they needed thin juice to keep up. Turn the power up too far and the coil vaporized juice faster than the wick could replace it, which meant dry, burnt hits.

That is why most e-liquid of that era was high in PG. The common blends, and how they felt:

• 80/20: little vapor and a moderately strong throat hit.
• 70/30: a little more vapor and a little less throat hit.
• 60/40: decent vapor with a noticeable but not overwhelming throat hit.

The middle ground: 50/50

As cartomizers gave way to clearomizers, and fixed-voltage batteries gave way to variable-voltage ones, coils wicked better and could take a little more power. E-liquid makers met them in the middle with 50/50 blends.

• 50/50: an even mix with good vapor and a soft throat hit.

For a long stretch, 50/50 was the go-to for many vapers because it balances flavor, smoothness and vapor, and plenty of people still prefer it. It is also a common base for nicotine salt juice in pod systems. Learn more in What Is 50/50 E-Liquid?

The sub-ohm era: high-VG juice

Then came more powerful mods and sub-ohm tanks, with bigger coils, more cotton and large wicking ports that could keep up with thick juice. At those higher wattages, many vapers found high-PG juice harsh. Around 2014, many e-liquid makers began releasing their flavors in high-VG blends.

• 40/60: noticeably bigger clouds and a reduced throat hit.
• 30/70: good vapor production and a minimal throat hit.
• 20/80: excellent vapor production and a very small throat hit.

A 30/70 blend became one of the most common ratios for bottled vape juice, because it works comfortably in most tanks and mods. Thick juice wicks slowly, though, so it can leave small pod and mouth-to-lung coils dry.

Why high VG suits powerful devices

VG boils at a much higher temperature than PG and is far thicker, so it needs more heat and more wicking to vaporize well. Sub-ohm coils deliver both, and VG rewards them with dense, smooth vapor. Push the same power through PG-heavy juice and the hit can feel sharp.

Expert notes: what PG and VG are

Propylene glycol (PG)

PG is made by reacting propylene oxide with water. It has been used for decades in foods, cosmetics and pharmaceuticals, as well as in industrial applications. That track record comes from eating it and putting it on skin, though, so it doesn’t tell you what inhaling it does. Boiling point: about 188°C (370.8°F).

Vegetable glycerin (VG)

VG, also called glycerol, is a simple polyol, sometimes described as a sugar alcohol. It is a colorless, odorless, thick liquid with a mildly sweet taste, and it is widely used in pharmaceutical formulations. Boiling point: about 290°C (554°F).

Nicotine changes the hit too

The ratio isn’t the only thing that shapes throat hit. Higher nicotine strengths add throat hit whatever the blend, and nicotine salts feel smoother than freebase nicotine at the same strength. See our guides to nicotine strength and nicotine salts.

Which ratio should you use today?

• Pod systems and MTL tanks: 50/50 or higher PG, often with nicotine salts.
• Sub-ohm tanks and RDAs: 70 percent VG or more, usually with lower-strength freebase nicotine.
• Disposables: the juice comes pre-filled, so the maker has already chosen the blend for the device.

When in doubt, check your coil’s packaging or your device manual, since some list the kind of juice they’re designed for. If your juice keeps tasting burnt, our guide on why your vape tastes burnt can help.

Bottles worth trying

Whatever your ratio, flavor is the fun part. Browse our flavor categories, or let the Zamplebox Club choose for you: you pick your nicotine strength and flavor families, and each month’s box is curated to your profile.

Common questions

WARNING: This product contains nicotine. Nicotine is an addictive chemical. For adults 21+ only.