How to save an image as a .jpg file (ending with .jpg, NOT .JPEG; read caption)?

(NOTE: I know .JPEG and .jpg are technically the same thing, but the website I want to upload the image on is refusing .JPEG files and requests a .jpg file only).

I have a Lenovo laptop with Windows 10.

I have an image that I can save as either a .JPEG or a .PNG on the program it is on, but the website I want to upload it to only accepts files ending in .jpg.
•I have tried naming a .JPEG version of the image as [image].jpg but the site still will not accept it and again requests a .jpg file.
•When I right-click the saved image and click "save as", the only option it gives me is to save it as a .JPEG for the .JPEG version and .PNG for the .PNG version (basically can't convert the file after saving it).
•I have also tried inserting it into online file converters, or putting it into programs like MS Paint or Autodesk Sketchbook to see if they had a .jpg file save option, but they all save it ending with a .JPEG extension.

1. Open the file in Notepad.
2. Go to File > Save as.
3. Put in .jpg next to the file name.

Just change the file extension from .jpeg to .jpg. How you do that will depend on what OS you're using. On the MacOS it's pretty simple, just single click on the file in Finder and change it. Not sure how Windoze handles that.

Use File Explorer (file manager) to rename *.JPEG to *.JPG.

"I have tried naming a .JPEG version of the image as [image].jpg but the site still will not accept it" This is usually due to the file name changing from image.jpeg to image.jpg.jpeg.

To save the file with a JPG extension in your program, click File and Save As (or the equivalent in the program), then type the complete file name enclosed in quotes, e.g., "image.jpg", and click Save.

Assuming it is Windows you are using & don't have filename extensions visible when you try to rename a JPEG to JPG which technically is image.JPEG you end up naming it image.JPG.JPEG

Enabling file extensions visible & then changing it should help.