Can You Plug an Inverter Into a Car Cigarette Lighter?

The short version: yes, with a power limit

A car's lighter socket is a 12V direct current (DC) outlet. An inverter turns that DC power into the 120V alternating current (AC) your household plugs expect. Many inverters are built with a lighter plug on the end for exactly this reason, so they work with no tools and no wiring.

The part that trips people up is how much power the socket can supply. Most car lighter sockets are fused for roughly 150W. An inverter rated higher than that can still plug in, but your car's fuse limits what you can actually draw from it. Pull too much and the socket fuse blows, and the inverter shuts off.

For a deeper look at models built for this, see our best power inverter for car cigarette lighter comparison.

Why the socket limits the inverter

Power equals volts times amps. At about 12V, a 150W load pulls roughly 12.5 amps from the socket. A 300W load pulls about 25 amps, which is more than a typical accessory circuit is designed to carry. The wiring behind a lighter socket is thin because it was designed for a phone charger or a tire inflator, not a heater.

That is why the rating printed on an inverter and the power you can use from a lighter socket are often different numbers. The rating tells you what the inverter can handle internally. Your car's fuse and wiring decide what the socket can deliver.

Check your owner's manual for the socket's fuse rating. It is usually listed in the fuse box diagram. If the manual gives a lower number than 150W worth of current, plan around the lower number.

Lighter plug or battery clamps?

Inverters generally connect in one of two ways. The right one depends on what you plan to run.

• Use the lighter socket for small electronics and charging.
• Use battery clamps when you need the inverter's full rating.
• If your device already charges over USB-C, a USB port may be all you need.

What the plug-in models on our spec sheet look like

Several inverters on our comparison page use a cigarette lighter plug as their connection. We compare published specifications, so the numbers below come from the listings, not from hands-on use.

Notice that the 300W and 400W models list a lighter plug even though the socket in most cars is fused lower. Treat those ratings as the inverter's capability, and keep your actual load modest when running from the socket.

Pure sine wave or modified sine wave

Pure sine wave output is the cleanest, and it suits sensitive electronics such as CPAP machines. Modified waveforms are fine for most chargers. If you are unsure, check the device's label or manual, and choose pure sine wave when the device is medical or has a motor or sensitive electronics.

Two of the BESTEK models above list pure sine wave output, and so does the 400W unit. Our comparison page covers more detail on each, and you can use our cigarette lighter inverter comparison to line them up by waveform, ports and warranty.

Can you convert a lighter socket into a regular outlet?

In effect, yes. Plugging in an inverter does exactly that: it gives you a standard outlet powered from the lighter socket. You do not need to change the car's wiring.

Some people want more power than the socket can give. That means running a heavier cable straight from the battery, with a proper fuse close to the battery. This is wiring work, and mistakes can cause shorts or fires. If you are not comfortable with it, ask a qualified installer or use battery clamps within the inverter's instructions.

Safety and setup steps

Inverters make household-voltage power, so treat them with the same respect as a wall outlet. Keep them dry and in a spot with airflow, because they warm up under load.

• Add up the watts of everything you plan to run and stay under your socket's limit.
• Plug the inverter in first, then turn it on, then plug in your device.
• Keep it off soft surfaces like seats or blankets, which block airflow.
• Do not run it for long periods with the engine off, since it can drain the battery.
• Never use clamps near the battery without checking polarity: red to positive, black to negative.
• Unplug it when you leave the car, and keep cables out of the driver's footwell.

Frequently asked questions

Will an inverter drain my car battery?

It can. An inverter draws power while it is on, and with the engine off that comes from the battery. Run the engine while using it for more than a short time.

Does a Tesla need a special inverter?

Some Tesla sockets run at a higher voltage than 12V. Look for an inverter that lists 11 to 17V input. Our data shows some BESTEK models list it, and the DrimMek model lists it as not compatible with Tesla 16V systems.

Why does my inverter beep or shut off?

That is usually a protection feature. It can mean low battery voltage, overload or overheating. Unplug the load, let it cool, and try a smaller load.

Can I run a microwave or space heater from the socket?

No. Those draw far more power than a lighter socket can supply. Stick to small electronics and chargers.