The Chemistry of Nicotine: Freebase, Salt Nic, and What's Actually in Your Vape
, by Liberty Vape, 7 min reading time
Unsure about Salt Nicotine vs. Freebase: What's the Difference? Discover how these two types of nicotine affect your vaping experience. Freebase offers a stronger throat hit in lower strengths, ideal for big clouds, while salt nicotine provides a smoother draw at higher strengths, perfect for on-the-go use. Find out which suits your vaping style!
Every bottle of vape juice and every disposable on our shelves comes down to one molecule: nicotine. But you'll see it sold two very different ways - "freebase" and "salt" (or "nic salt") - and the labels can be confusing. The short version is that it's the same nicotine either way; what changes is a bit of chemistry that decides how it feels, how strong it's sold, and which device it belongs in. Here's the whole picture, from the molecule up to the product page.
What is nicotine?
Nicotine is a chemical naturally produced by plants in the nightshade family, which includes such familiar plants as tobacco, tomatoes, and potatoes. These days it's more likely to be synthesized in a production facility than extracted from a living plant. In the plant itself, nicotine acts as a pest repellant - a similar role to the one capsaicin (the spicy chemical in hot peppers) plays elsewhere. Chemically, it's an alkaloid, a very broad class of chemicals. Alkaloids are organic (carbon-based) chemicals that include nitrogen and are typically bitter in taste.
The name comes from Jean Nicot de Villemain, the first person to bring tobacco to France. The tobacco plant's biological name, Nicotiana tabacum, is in his honour, and from it we derive the chemical name "nicotine."
The structure of the nicotine molecule
Freebase nicotine's chemical formula (you don't need to remember this for the test!) is C₁₀H₁₄N₂, indicating that its main components are carbon and hydrogen, with a little nitrogen on top. Structurally, nicotine is built from two atomic rings, pyrrolidine and pyridine. There are also two chiral - or mirror-image - versions of nicotine: levo-nicotine (left-handed) and dextro-nicotine (right-handed), with levo-nicotine being the familiar form found naturally in tobacco.
When you inhale or otherwise ingest nicotine, it enters the bloodstream and interacts with what are known as nicotinic acetylcholine receptors, found in multiple places throughout the body, producing its familiar effects.
Freebase vs. salt: it comes down to pH
Freebase nicotine is alkali - it has a pH above 7, or is "basic." That single trait is behind its harsher hit and faster absorption: in this form, nicotine moves across cell walls more easily. It's the original, unmodified form that's been used in vaping (and in cigarettes) for decades.
To create a version that stays smooth even at higher doses, freebase nicotine is reacted with a weak acid to produce a salt - chemist-speak for a neutralized acid-base combination. Common acids used are benzoic acid (found in many plants, including cinnamon), lactic acid (the same acid your muscles make when you exercise, also found in yogurt and many foods), and levulinic acid (formed by the chemical processing of sugar), among others; the small differences between them have slight but meaningful effects on the finished salt. Going back to the structure above, the weak acid protonates - adds a hydrogen ion to - the nitrogen of the pyrrolidine ring, lowering the pH and taking the edge off the throat hit.
There's a second factor at play, too: how each form is aerosolized, or turned into the inhalable particles you actually breathe in. Salt particles tend to be smaller and can be inhaled more readily than freebase ones. Between the pH and the particle size, the two forms end up suited to very different devices - which is where the buying decision comes in.
Freebase nicotine
Because freebase performs well at lower strengths and higher power, it's the standard for bottled vape juice used in refillable devices - including bigger sub-ohm setups built for large clouds and direct-to-lung (DTL) draws. Its more pronounced throat hit is why it's usually sold in lower strengths, commonly 3 mg, 6 mg, and 12 mg, so the hit stays comfortable as you inhale.
Salt nicotine
Because the acid smooths out the draw at high strength, salt nic can be run at a higher concentration - typically 20 mg in Canada - without the harshness you'd get from freebase at the same level. Many people also find salt nic satisfies a craving faster. That smoothness at high strength is exactly why salt nic is the standard in disposables and pod systems, which are designed for a tighter, cigarette-like mouth-to-lung (MTL) draw at lower power.
What about BOLD50?
You may also come across "BOLD" products, usually labelled BOLD35 or BOLD50. The number is a throwback, not a nicotine count - these are built to feel like the old 35 mg and 50 mg products that were sold before Canada capped nicotine at 20 mg/mL. BOLD is still 20 mg/mL and fully compliant; the "50" just signals that it's meant to replace the experience of the old 50 mg strength that's no longer available here.
Here's how it connects to the pH idea above. Salt nic adds acid to lower the pH and smooth out the throat hit. BOLD does the opposite on purpose: it uses less acid in the salt formulation, which raises the pH back up and brings back a stronger, more peppery throat hit - closer to what those old high-strength products delivered. BOLD50 is the boldest of the range, giving the biggest, most cigarette-like hit while staying at the legal 20 mg. It's aimed at heavier former smokers who find standard 20 mg salt nic too smooth.
Throat hit and strength, side by side
The quickest way to think about it: freebase gives a bigger throat hit and is run at lower strengths in higher-powered, refillable gear; salt nic stays smooth at higher strengths and is run in lower-powered disposables and pods. Neither is "better" - they're built for different styles of vaping.
How nicotine strength is measured
Whichever form you choose, strength is shown one of two ways: in milligrams per millilitre (mg/mL) or as a percentage - and they're just two ways of writing the same number. A 20 mg/mL salt is a 2% nicotine solution; a 3 mg/mL freebase is a 0.3% solution. The strength and nicotine type are listed on every product page, so you can match the form to the device you're using.
And if your answer is "none," that's a legitimate choice too - 0 mg sits at the very bottom of the same scale. We cover the zero-nicotine lines we carry in a companion guide, Going Nicotine-Free: Your 0mg Options at Liberty Vape.
Which one is right for you?
Salt nicotine tends to suit you if you want higher nicotine, a smooth draw, a compact device, and a cigarette-like MTL style - or if you simply want to grab something and go. Freebase tends to suit you if you prefer a lower nicotine strength, enjoy a stronger throat hit, like bigger clouds and a DTL draw, and don't mind refilling and maintaining a device.
What to shop at Liberty Vape
If salt nicotine sounds like your fit, look at our disposable vapes and pods - both run salt nic and are ready to use out of the box. Lines like the Mr Fog Aura 60K and the Versa X 40K pods are 20 mg salt-nic options.
If freebase is more your speed, browse our vape juice in 3 mg through 12 mg strengths, and pair it with a refillable setup from our devices & hardware. Some of our e-liquid lines are also offered in salt-nic versions, so check the strength options on each product page.
Not sure which way to go? Start from the device - a disposable or pod points you to salt nic, a refillable tank points you to freebase - and the rest tends to follow.
These products contain nicotine, which is addictive. Intended for adults of legal vaping age only.