Can I Use A 12V Adapter For 9V Router?

Routers are necessary to access the internet via Wi-Fi. However, if your old plug or adapter breaks that you used to power up your router, you might want to use a spare from the already available ones.

Let’s consider the fact that you might be in an emergency situation, and there are no other choice adapters in front of you other than the 12V one. In such circumstances, you might be thinking: can I use A 12V adapter for 9V router?

The truth is: you can’t use a 12V adapter for a 9V router as it delivers more voltage power than required. It is nearly impossible for a 9V router to work with a 12V adapter in such cases. While connected, the router will not work and some of its internal parts might get fried apart due to higher voltage.

Well then, are you interested to know more about two different components with different voltage requirements? Scroll down without any further ado.

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  • A 12V adapter will not work on a 9V router under normal circumstances.
  • In the case where the 12V adapter works in providing electricity to the 9V router, the energy will never be enough.
  • When the setting works, 78 percent of the energy will be converted into heat which will burn the internal fuse of the router.
  • Use a multimeter to check whether the voltage requirement of the adapter matches the voltage of the router.
  • You can make use of stabilizers or regulators to use a 12V adapter with a 9V router.

Can I Use A 12V Adapter For 9V Router?

No. Under normal circumstances, it should be impossible for you to get your 9V router to work with the 12V adapter. This is because the 9V router is simply not strong enough to cope with the 12V electricity that the adapter will provide it with and some of the internal parts of the router get fried due to higher voltage.

Can I Use A 12V Adapter For 9V Router

However, there are some cases where it did work. Even then, this is not worth it. This is because, in 2 out of 5 cases where this setting worked, the fuse of the router burnt up.

According to circuit calculations, a 12V adapter is only able to provide a small amount of electricity that will never meet the needs of the router. Additionally, about 78 percent of the total electric energy will be converted to heat. This heat is responsible for burning the fuse.

If you are using a very old router that has no fuse, expect the entirety of the router’s internal parts to get burnt. Furthermore, do not expect the router to be salvageable anymore.

Is It Safe To Use A Different Power Adapter For My Router?

You need to think about several dangers when connecting your router to a different power adapter than the one that comes by default.

Is It Safe To Use A Different Power Adapter For My Router

While it is not as dangerous as long as you have a fuse built inside your router, using a power adapter that has a huge voltage or current difference compared to your router can cause preposterous results.

We have compiled some of these dangers that you might potentially face based on different scenarios when using an adapter and router with two different power requirements with a significant difference.

When The Current Is Too Low:

If the current of your adapter is lower than the requirement of the router, it is the adapter that would be affected instead of the router. This is because the router would attract more electrons from the electric transformer than the adapter could cope with.

As a result, the adapter might overheat and eventually cause the overall voltage to drop significantly. Additionally, the fuse inside the adapter could also blow out, causing the entire adapter to stop supplying energy.

When The Current Is Too High:

If the current of the adapter is higher than the current rating of the router, there shouldn’t be any major problems with the router. This only means that the adapter will not be worked to its full potential since it does not have to supply all of the electrons that it can allow inside.

However, do note that these extra electrons might cause the router or the sires to heat up slightly. Then again, this is not a significant danger, so you shouldn’t have to worry about this.

When The Voltage Is Too High:

This is the most dangerous as well as the most common scenario seen when using a different adapter for your router. In most cases, the router should have its fuse blown out since too much heat is produced inside its internal components and overheat the router.

In case there is no fuse present inside the router, the entire router might be damaged beyond repair. In extreme cases, even the wire might catch flame.

When The Voltage Is Too Low:

If the voltage requirement of your router is higher than what the adapter can provide, there will not be any disastrous effects that coil heating effects on any of the devices.

However, do expect the total power that the router can receive to not be consistent. This is because the total power input given to the router will never meet the requirement set by the router.

What Is The Difference Between 12V And 9V?

In terms of the voltage needed to produce a certain amount of current, there is not much difference between 12V and 9V. In fact, this small difference of 3V is a simple drop in the ocean for most larger devices that need tremendous amounts of voltage to feed the high power demands.

Difference Between 12V And 9V

However, if we are going to think in more technical terms involving smaller devices like the router and adapter, this small difference can make a large point.

For instance, let’s consider two circuit and bulb systems with a fixed amount of resistance in the wire. The system which receives the larger amount of 12V allows more electrons to pass through the wire compared to the system receiving 6V.

Since there are more electrons in the 12V circuit, the current input to the bulb will be higher. This means that more energy conversion and power production is going on in the 12V circuit than in the 6V circuit.

This is a difference of about 18.72×10^18 electrons between 12V and 6V circuit systems.

How To Use A 12V Adapter For A 9V Router?

Well, you actually can’t make use of a 12V adapter for a 9V router. Even if it works, energy production is highly inefficient, and it is also dangerous.

How To Use A 12V Adapter For A 9V Router

However, if you still want to make use of the above setting, then it is advised that you connect the two devices via regulator IC-7809. It is a very small appliance and is completely inexpensive, costing as low as a dollar.

Additionally, you can also make use of circuit stabilizers to convert the voltage supplied by the adapter into 9V for the router.


While certain schematics are built around a certain router or modem, allowing it to take in the voltage from a 12V adapter while being 9V itself, do not trust these contrabands.

The components built inside them are not foolproof, and even a slight fluctuation of the voltage supplied can cause them to act up permanently.

We advise you always to use the rightful specifications that match both the requirements of your router and adapter requirements. Only then would you be able to use both of these appliances to their best potential while erasing any possible issues that might arise otherwise.

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