Nintendo (NES) ROM Format
To edit NES file, we strongly recommend installing software that works with NES files. There are many tools known as NES Online Editors, but it is not certain that they operate in a way that keeps the data contained in the file safe.
Remember, that not all of the mentioned programs will allow you to edit the NES file. If you want, you can learn more about the NES file extension.
This is definitely the surest way. Choose one of the programs that support the NES file extension, open your file and check the editing options. It's safest to download the software from the developer's website. You can find direct links to the creators' websites on the subpages of each application. Below you will find some examples of software programs that support the NES file (so it is very possible that they can edit files in NES format).
All available programs supporting the NES file
Remember that many file types have a text format and you can preview their contents by opening them, for example, with Windows Notepad. However, it's dangerous, you can permanently damage your NES file. If you make inappropriate changes and save the file, it may happen that you do not reopen the NES file.. For this reason, try to use software created to edit NES files.
It can definitely be said that any of the list of programs that support the NES extension should be able to edit the NES file. Use other options if you still haven't found a way to edit NES. Below are tools that allow you to edit NES online files.
Free Online File Edit Service
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