USB Voltage Test: How Do I Measure The Voltage of A USB port?

You can measure the voltage coming out of a USB by plugging the USB multimeter into the port. The multimeter does not require external power since it automatically turns on once you plug it into the port. You can read the results on your screen since it’s just that simple.

If you have a USB port that is not working appropriately or does not give you the current or voltage that it is supposed to provide, or you love electronics.

Other possible ways can be:

You want to monitor the USB port current and voltage; that’s why you are measuring these qualities.
You don’t know the quantity of power your power bank delivers via its USB port. You want to crosscheck its ratings or troubleshoot it.
You have a variety of mixed USB cables, and you want to get rid of the bad ones.

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The first method: using a multimeter

Steps to measure the USB Voltage using a multimeter

One of the requirements that you should have is spare USB cables. The kind of USB cable is based on the type of port you need to measure.

Cut the cable at the center and mark the power and the ground line (power line is red and ground line is black)
Correctly insert the USB cable in the port.
Turn on the multimeter and choose DC voltage (if your multimeter is manually set, the DC voltage range is up to 10V or 20V is available.
Connect the red USB cable wire with the red multimeter probe
Connect the black USB cable wire with the black multimeter probe
Check the results on your display. It’s simple as that, but you lose your USB cable.

The challenge with this method is that you need a spare USB that should work and have a fine shape. If you don’t have a multimeter, then it means you require a spare USB cable and a good multimeter.

The other problem is that you can’t know what happens to voltage when loading occurs. To solve the challenge of connecting the load, you need to join the remaining USB half cables back, and then you will be able to connect your load. (The multimeter is still being connected).

The second method: using a dedicated USB multimeter

As the name proposes, a USB multimeter is a multimeter that is used to measure port voltage and current. Apart from the two measurements, it can give capacity measurements such as checking phone battery capacity.

How to use the USB tester/multimeter

The use of a USB multimeter is very simple. Due to its simplicity, most people prefer using it to look at their device’s ports.

Steps to measure the USB Voltage using a dedicated USB multimeter

Choose the port that you want to check.
Ensure that you have keenly marked the type of your port, and based on its type, you have bought the correct USB multimeter.
Insert the USB multimeter into the port.
The multimeter does not need any external power; hence it will automatically turn on once you plug it into the port.
Voltage is measured in terms of volts(V).

If the display voltage appears bitchy, normally, it should be around 5V for the majority of the USB ports. If yours is not this way, it means your USB port is not okay.

Do not forget that 5V is mostly for the mobile and computer charger USB outputs. If you insert the USB multimeter into a device such as a power bank, you may get other voltage levels.

Conclusion

How do I measure the voltage coming out of a USB? It’s very easy to measure the voltage coming out of a USB. All you need to do is simply plug the USB multimeter into the port.

The multimeter does not require external power since it automatically turns on once you plug it into the port. You can read the results on your screen since it’s just that simple.

There are two ways that you can use to measure the voltage coming out of a USB:

Using a multimeter

Cut the cable at the center and mark the power and the ground line (power line is red and ground line is black)
Correctly insert the USB cable in the port.
Turn on the multimeter and choose DC voltage (if your multimeter is manual, set the range of the DC voltage up to 10V or 20V is available.
Connect the red USB cable wire with the red multimeter probe
Connect the black USB cable wire with the black multimeter probe
Check the results on your display. It’s simple as that, but you lose your USB cable.

Using a dedicated USB multimeter

Choose the port that you want to check
Ensure that you have keenly marked the type of your port, and based on its type, you have bought the correct USB multimeter.
Insert the USB multimeter into the port.
The multimeter does not need any external power; hence it will automatically turn on once you plug it into the port.
Voltage is measured in terms of volts(V).