Start11 Win11 Style Custom Background Image Size

I did a quick search and didn't see anything addressing this specifically.

What is the ideal size for a Start 11 custom background image for the Start Menu in Windows 11 mode?   I can trial and error it, but I keep getting a distorted or stretched image and I'd like to make a custom image that fits perfectly without scaling.

Thanks, and sorry if this is clearly addressed elsewhere and I just didn't look hard enough.

**Resolved** Found a pre-canned image in the default folder for this purpose, and the answer appears to be 1000 x 563.