Every coil has a number stamped on it. 0.6 ohm. 0.8 ohm. 1.2 ohm. Nobody explains what you are supposed to do with that number, so most people fit the coil, run whatever wattage the device defaults to, and put in whatever e-liquid is already open.
That works until it does not. Then you get a burnt hit, or thin flavour, or a coil that dies in three days. All three usually come down to the same thing: the resistance, the power and the e-liquid are not matched to each other.
This guide covers what the number means, what wattage suits it, and which e-liquid to pair with it.
TL;DR
- Lower resistance means more power, more vapour and a looser draw. Higher resistance means less power, less vapour and a tighter draw.
- Below 1.0 ohm is usually direct-to-lung. 1.0 ohm and above is usually mouth-to-lung.
- Thicker, higher-VG liquid needs a lower-resistance coil to wick properly. Thinner, higher-PG liquid suits higher-resistance coils.
- The wattage range printed on the coil is the authority. Start at the bottom of it and work up.
What the ohm number actually means
Resistance is measured in ohms and it decides how much power flows through the coil at a given wattage.
A low-resistance coil lets more current through. It heats faster, vaporises more liquid per second and produces more vapour. It also drinks e-liquid faster and drains the battery faster.
A high-resistance coil restricts the current. It heats more gently, produces less vapour and a tighter draw, and makes both the liquid and the battery last longer.
Neither is better. They are built for two different ways of vaping. Sub-ohm coils, meaning anything below 1.0 ohm, are built for direct-to-lung: a loose, airy draw straight into the lungs. Coils at 1.0 ohm and above are built for mouth-to-lung: a tighter draw held in the mouth first, closer to how a cigarette is drawn.
If a coil feels wrong, it is worth checking you are not simply running the wrong style for it. That mismatch is the single most common cause of "this coil is rubbish".
The pairing table
These are typical ranges across common UK coils. The wattage range printed on the coil itself always overrides this table — manufacturers build to their own specification and the printed range is the one that matters.
| Coil resistance | Typical wattage | Vaping style | E-liquid that suits it |
|---|---|---|---|
| 1.2 – 1.6 ohm | 8 – 14 W | Mouth-to-lung | 50/50 PG/VG |
| 0.8 – 1.0 ohm | 12 – 18 W | MTL / restricted DTL | 50/50 to 60/40 VG |
| 0.6 ohm | 15 – 25 W | Restricted DTL | 60/40 to 70/30 VG |
| 0.4 ohm | 20 – 35 W | Restricted DTL / DTL | 70/30 VG |
| 0.2 – 0.3 ohm | 40 – 70 W | Direct-to-lung | 70/30 VG |
| 0.15 ohm | 60 – 90 W | Direct-to-lung | 70/30 VG or higher |
Two rules of thumb sit behind the whole table. Halve the resistance and you roughly double the power the coil wants. And the more power a coil takes, the more liquid it has to pull through per second, which is why higher-power coils need thicker high-VG liquid and wider wicking channels to keep up.
Why PG/VG ratio matters more than people think
PG and VG are the two carrier liquids in every bottle. The ratio changes how the liquid behaves in the coil.
- Higher PG (50/50 and similar) is thin. It wicks quickly through narrow channels, carries flavour sharply and gives a firmer throat hit. It suits higher-resistance MTL coils, which have small wicking ports and cannot pull thick liquid fast enough.
- Higher VG (70/30 and above) is thick and sweet-tasting. It produces denser vapour and a softer throat hit. It needs the wide wicking ports and higher power of a sub-ohm coil.
Put 70/30 VG in a 1.2 ohm MTL coil and it will wick too slowly, dry out and burn. Put 50/50 in a 0.15 ohm coil at 80 watts and it will flood, leak and spit. Neither is a faulty coil. It is a mismatch.
If you want the ratio question on its own, we have a fuller breakdown in the PG/VG ratio guide.
Nicotine strength follows the same logic
The more vapour a coil produces, the more nicotine reaches you per puff. So strength should come down as resistance comes down.
- MTL coils, 1.0 ohm and above: higher strengths are normal here, and nicotine salts are the usual choice because they feel smoother at higher strengths than freebase does.
- Sub-ohm DTL coils, 0.4 ohm and below: low-strength freebase only. High-strength salts in a sub-ohm coil deliver far more nicotine than intended and are unpleasant with it.
- The middle ground, 0.6 to 0.8 ohm: either can work. Start low and adjust.
Browse freebase e-liquid for sub-ohm setups. All nicotine products on this site are for adult smokers and vapers aged 18 and over.
How to set the wattage without guessing
- Read the range printed on the coil. Every replacement coil has one. If the coil is already fitted, the box it came in has it too.
- Set the device to the bottom of that range and prime the coil properly: fill the tank, wait five minutes, and take two or three gentle draws before firing at full power.
- Go up in 2 to 3 watt steps. Stop when the flavour is at its fullest.
- If it tastes harsh or burnt before it tastes full, you have gone past what the wick can keep up with. Drop back 5 watts and check the liquid is thick enough for the coil.
Wattage that is too low is a wasted coil rather than a damaged one — weak flavour, thin vapour, nothing broken. Wattage that is too high genuinely shortens coil life, and it is the most common reason a coil that should last a fortnight dies in a few days. If you are getting a burnt taste, the burnt taste guide works through every cause in order.
Device-specific ranges
Pod kits usually pick the wattage for you based on the pod fitted, so the table above is a sanity check rather than a setting. For the OXVA Xlim family, which is the most-asked-about pod range on this site, the wattage behaviour for each coil is covered in the Xlim Pro 2 review, and replacements are in the Xlim pods collection.
For adjustable sub-ohm devices, where you set the wattage yourself, the range in the table is the starting point. See the sub-ohm vape kits range.
If the device is reading a resistance that does not match the coil, or refusing to fire, that is a contact or chip issue rather than a pairing one — see ohms too low: causes and fixes.
Conclusion
Match three things and most coil complaints disappear: the resistance to the way you want to draw, the wattage to the printed range, and the PG/VG ratio to the resistance. Get those lined up and coils last longer, flavour is fuller and burnt hits become rare.
Frequently Asked Questions
What wattage should I use for a 0.6 ohm coil?
Typically 15 to 25 watts, for a restricted direct-to-lung draw. Start at 15, go up in 2 to 3 watt steps, and stop when the flavour is fullest. The range printed on the coil overrides this.
What is the best e-liquid for a 0.15 ohm coil?
A high-VG liquid, usually 70/30 or thicker, at a low nicotine strength. A 0.15 ohm coil runs at high power and produces a lot of vapour, so thin 50/50 liquid will not wick fast enough and high-strength nicotine will be far too much.
What PG/VG ratio suits a 0.8 ohm coil?
50/50 to 60/40 VG. A 0.8 ohm coil sits between mouth-to-lung and restricted direct-to-lung, so both work. Go closer to 50/50 for a tighter draw and more throat hit, closer to 60/40 for more vapour.
Can I use nicotine salts in a sub-ohm coil?
Only at low strength, and it is not the usual pairing. Nicotine salts are made for higher-resistance mouth-to-lung coils. In a sub-ohm coil producing much more vapour per puff, a high-strength salt delivers far more nicotine than intended.
Does running higher wattage kill coils faster?
Yes, once you go beyond what the wick can keep up with. The coil vaporises liquid faster than the wick can replace it, the wick dries at the edges and scorches. Staying inside the printed range is what makes a coil last.
Why does my coil taste burnt at the right wattage?
Usually priming or e-liquid thickness rather than the wattage itself. A new coil needs the tank filled and five minutes to soak before the first firing, and liquid that is too thick for the coil's wicking ports will not keep up whatever the power setting.
