PG and VG: the two ingredients that decide how a vape feels
Every e-liquid is mostly two substances: propylene glycol (PG) and vegetable glycerin (VG). Everything else — nicotine, flavourings, and in some cases a little water or ethanol — is a small fraction of the total. The ratio between PG and VG is the single biggest reason two liquids at the same strength and flavour taste and feel completely different.
What each one does
| PG (propylene glycol) | VG (vegetable glycerin) | |
|---|---|---|
| Throat hit | Stronger | Softer |
| Vapour volume | Thinner cloud | Thicker cloud |
| Flavour carrier | Carries flavour sharply | Carries flavour more softly |
| Viscosity | Thin, wicks quickly | Thick, wicks slowly |
| Typical strength in a pod | Good at low power | Needs more power to wick well |
A high-PG liquid gives a firmer throat hit, which matters if you are coming from cigarettes and want that sensation. A high-VG liquid produces more visible vapour and a smoother inhale, but it is thicker and can struggle in a tight, low-power pod.
Common ratios and who they suit
| Ratio (PG:VG) | Character | Suits |
|---|---|---|
| 70:30 | Firm hit, thin vapour | Low-power pods, cigarette-like feel |
| 60:40 | Balanced, slightly firmer | Most refillable pods |
| 50:50 | Balanced | Pods and most disposable devices |
| 30:70 | Smooth, big clouds | Higher-power systems with wider coils |
Disposables are usually in the 50:50 region because that ratio wicks reliably in a small, low-power device and gives a balanced hit. If you have ever compared two disposables and found one harsher than the other at the same stated strength, the PG/VG ratio is one of the likely differences. Refillable liquids in the balanced range are listed under e-liquid.
Why ratio matters more than it looks
Viscosity is the practical constraint. A thick, high-VG liquid moves slowly through a narrow wicking channel. In a low-power pod that mismatch produces dry hits, which taste burnt — the problem described in why a vape tastes burnt. High-PG liquid is the opposite: it wicks easily but can flood a wide-coil system, causing gurgling and spitback, both covered in gurgling and bubbling and spitting juice.
If you are troubleshooting a leaking device, viscosity is also a factor — see why a vape leaks.
PG, VG and nicotine delivery
PG carries nicotine and flavour more aggressively than VG. In practice this means a higher-PG liquid can feel like it hits faster and harder even at the same concentration, because the sensation arrives more sharply on the throat and upper airway. VG is smoother, so the same strength can feel gentler.
That is one of several reasons the same stated strength behaves differently across devices; the fuller picture is in nicotine strength for pods vs disposables. The question of how much nicotine you actually absorb is handled in nicotine absorption.
Sensitivity and intolerance
A minority of people report throat irritation, a dry mouth or a cough that they associate with PG rather than with nicotine. This is usually a sensitivity rather than an allergy, and the usual approach is to try a lower-PG blend. Dry mouth in particular is common with vaping generally, independent of ratio; see vaping and dehydration.
If you suspect a genuine reaction rather than irritation, stop using the product and seek medical advice. This article is general information, not medical advice.
Practical rules of thumb
- Small, low-power device: stay around 50:50 or higher PG. Thick liquids will not wick fast enough.
- Higher-power device with a wide coil: higher VG wicks properly and produces a smoother inhale.
- Wanting a firmer hit: increase PG rather than increasing nicotine — you are already capped at 20 mg/ml.
- Burnt taste with no other explanation: check the ratio before replacing hardware. See burnt taste troubleshooting and priming a coil.
- Change one thing at a time. Ratio, strength and device all interact; altering two at once makes the result impossible to read.
Frequently asked questions
Is PG or VG safer?
Both are long-used in inhaled products and neither is considered the safer option in general terms. The relevant variable for most users is comfort and device compatibility rather than safety. This is general information, not medical advice.
What ratio do disposable vapes use?
Most are around 50:50, because that ratio wicks reliably in a small, low-power device.
Why does higher PG give a stronger throat hit?
PG carries flavour and nicotine more aggressively and produces a firmer sensation on the throat than VG.
Can I mix two liquids with different ratios?
Yes, within reason, but the result sits between the two and the viscosity changes accordingly. Mixing is not recommended for sealed disposable devices, which cannot be refilled — see can you refill a disposable.
Does VG produce more vapour?
Yes. VG is the main driver of visible cloud volume.
