What Is MTU In Networking?- Simply Explained

MTU or Maximum Transmission Unit is a networking term used to indicate the maximum packet size that can be transmitted over a network. 

Tired of trying to make your internet connection faster? Or just looking for a way to optimize your connection?  

Well, what if I tell you it can be done without spending any money! 

Yes, you heard it right. You can optimize your connection only by setting up a suitable  MTU for your particular usage as well as your home network.

Don’t get scared already! 

Because this article is going to help you find your suitable MTU, set up the MTU, and discuss everything you need to know about MTU. 

So, stay tuned. 

But first, let’s find out what MTU is in detail.

What Does MTU Stand For?

MTU stands for Maximum Transmission Unit, which means the highest packet size your network can transmit. Let me make it simpler. 

The data you sent over the internet is broken down into smaller blocks. We call these blocks packets. Each packet contains a header and a payload or data. The header contains the packet source, a destination address, etc. This header data is used to reassemble the smaller packets into the original file to view. 

For example, when you load an image on the internet, the image data is sent from a web server to your device, the image constituents travel over the Internet as a series of packets. Then your receiver device reassembles the packets and you can view the image.

Now MTU is the maximum packet size your network can pass on. But what is the size of the MTU?

MTU Size

For ethernet standards, the MTU size is 1500 bytes. 

As we mentioned before, the data packets contain a payload or the actual data, and the (TCP & IP) header

Each header has a size of 20 bytes, totaling 40 bytes. If we subtract the 40 bytes from 1500 bytes then 1460 bytes remain for the actual data. 

However, some devices support Jumbo Frames meaning the MTU can be up to 9000 bytes. Newer Ethernet standards support  Jumbo Frames. They are mostly found in data centers. But it’s still rare in WAN. 

But what if a data packet exceeds the MTU? 

Well, then fragmentation occurs. 


When a data packet size exceeds the MTU limit of a network then the router or the receiver device of that network breaks the data packets into smaller packets and transmits them into the network. 

However, newer IPv6 protocols don’t support fragmentation and if you have a firewall then you might face problems with fragmentation too. 

Well, we have learned the basics of MTU. Now, let’s discuss about optimizing your MTU settings. 

The first step of optimizing the MTU setting is finding the MTU settings on your router.

How To Find The MTU Settings On Your Router

Finding the MTU settings on your router is a pretty easy process. Just follow the below instructions carefully. 

  1. First, go to the browser using any device connected to your network. 
  2. Now go to your router website or type the IP address you will find below your router. 
  3. Then you will be redirected to a log-in page. 
  4. Log in using your admin id and password. If you don’t know these login credentials then try using admin in the admin name and password in the password section. 
  5. After logging in click on Network >WAN > MTU. 
  6. If you don’t find it in the network then go to Advanced > Network > WAN > MTU or Advanced > Network > Internet. 

You can also look for MTU on the smartphone app of your router.  

Well, we have found out the MTU settings. But before changing it, we need to find out the optimal MTU for your network. 

How To Find The Optimal MTU Size For Your Network

The best way to find the proper MTU size for your network is to perform a ping test. It’s a pretty easy process.  

You just need windows or MAC devices and follow the instructions below. 

But first, you need to go to the Command prompt of your device. 

To Open Command Prompt In Windows 

  • Go to the search bar of your Windows device. 
  • Then Type in CMD

Now Open the app and you will be redirected to an interface like below.

Well, you have successfully opened the command prompt.

To Open Command Prompt In MAC

The process is pretty similar 

  • Type terminal on the search bar of your MAC.

Now open the app.

Now let’s start the ping test.

Ping Test To Find The Optimal MTU

To perform the ping test please follow the below instructions carefully. 

  1. After opening the CMD panel/ Terminal copy this instruction ‘Ping www.smartnetworkgeek.com -f -l 1500 and paste it to  CMD Panel/ Terminal. 
  2. After that press enter

3. If you find fragments like above then reduce the packet size 10  like below

4. If you find fragments again then keep trying with 10 less

5. Once you find there is no fragmentation, now keep increasing the packet size by 1 or 2 bytes. Like below.

6. Keep increasing till you find the optimal one.

For me, it’s 1472 bytes. But that’s not the optimal size you should set on your router or device. 

Because as we have talked before every packet contains a header and it has a total size of 28 bytes. 

So, add 28 with the number you find on the ping test. 

For example, I have found 1472 in the ping test. Adding 28 with 1472 will make it 1500 bytes. 

So, my optimal MTU size will be 1500 bytes. 

But how can you change the MTU size of your network? 

How To Change The MTU Size Of Your Network

MTU settings can be changed in 2 ways. You can either set it directly on your router. If you do this then this will change the entire MTU size of the network. Or you can change the MTU settings of each individual device according to the device’s need. 

Now let’s learn about both

  1. How To Change MTU On Router

If you already found your MTU settings like we have talked about in the previous part of this article, then you don’t need to work much. Just change the MTU size to your newfound optimal size. 

If you haven’t done the below part then go to the How To Find The MTU Settings On Your Router part of this article. Follow the instructions and change the MTU settings. 

After that restart your router. 

This is how you change the MTU on the router. But if you want to change the MTU size for individual devices then follow the below steps.

2. How To Change MTU On Windows 10

To change MTU size on individual devices, 

  • First, Go to the command prompt. 
  • Then paste this instruction netsh interface ipv4 show subinterfaces and hit enter. 

After finding an interface like the above type in this instruction netsh int ipv4 set subinterface “Ethernet” mtu=1472 store=persistent and hit enter.

Your MTU size for this particular device is set. Just remember to type in your optimal MTU “netsh int ipv4 set subinterface “Ethernet” mtu=1428 store=persistent” in this. 

Now we have found the best optimal MTU and set it up. But what’s the plus point of this? 

Changing the MTU settings to an optimal one can significantly boost your network performance. Moreover, it can slightly increase the network speed too. So, the time you spent on changing the MTU does not get wasted. 

Now let’s find out some of the most common questions and confusions on MTU. 


What Is The Best MTU Size For Streaming?

Actually, there are no specified MTU settings for streaming. It completely depends on your connection type or network. 
Moreover, streaming speed depends on the distance of the server you are streaming from. However, it can be different for different people. 

So, if you really want to change MTU for a device for streaming. Then find out the optimal MTU for the website you are streaming. Follow the same instructions we have talked about before. Just in the ping test ping the website you are streaming from. 

If you find a different optimal MTU for that particular website then set that MTU. 

There is no evidence that changing MTU makes streaming better. But some people believe lowering the MTU size can reduce ping and lag. Resulting in lower latency. 

So, you can try it. Do let us know in the comments if you find it working.

What Is The Best MTU Size For Gaming?

Like streaming, there is no real evidence that changing the MTU can improve the ping and lag. But changing the entire network MTU to an optimal will work better from our perspective. 

However, if your want to change the MTU settings on your console then follow the below steps

What Is Mtu Settings Ps4?
To find your MTU on your Ps4

1. Go to Settings>Network>Set Up Internet Connection. 
2. Then run all the settings as they are in automatic
 3. However, switch to Manual for the MTU settings,
4. Then keep lowering the MTU value on your PS4 by manually a lower MTU value each time.input the value you want.
5. Keep testing your internet connection with each progressively lower MTU value until your connection test screen displays that “packets are no longer able to be fragmented”
6. Then add 28 with it. That should be the optimal MTU for your Ps4.

That’s how you set up the optimal MTU in Ps4.

Is Higher MTU Better?

Yes, higher MTU can bring more efficiency in data transmission. Because in a higher MTU each packet carries more data. Resulting in better overall efficiency. 

However, larger packets might get fragmented. As we have learned before, fragmentation can result in lower transmitting speed, data loss, and overall bad network performance.  

So keeping your MTU to the optimal is a better option.

What Is The Best MTU Size For A Tp-Link Router?

Actually, there is no particular MTU size that’s better for individual routers. It’s true for TP-link routers too.

However, TP-link suggests keeping the MTU lower than 1492 bytes for PPPoE connectivity. 

So, using your optimal MTU for TP-link routers will work fine.

Moreover, for VPN connections the MTU is different. As the data packets are encrypted.


This is everything you must know about what is MTU in networking. I tried to make all the networking terms as easy as possible. Because it will help you optimize your network easily. 

However, keep in mind that choosing the wrong MTU setting can cripple your router and reduce your overall network speeds to an unbearable level. So, be very careful while performing the above tests and changing your MTU size. 

If you have any questions or confusion, let us know in the comments. 

Like always stay tuned to us for more fun blogs like this.

also, don’t forget to check our latest article about the best wireless routers.

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