What size font?

12 pt bold with 16 pt for caps

Times New Roman 12 point because it's easy to read.

I prefer using Times New Roman size 14. But I do change based on the needs of my client. 

The industry standard is 12 pt.

Times New Roman at 12 point font, double spaced. I also use Grammarly, to supplement my...writing challenges.

I use what is generally accepted as a standard, especially for publishers and agents: Times New Roman at 12 point font, double spaced.

I use new times roman or 12 because the easiest for people to read. Plus it's close to what you had back on typewriter days of pics and elite. I hope this answers your question.

12

There are so many answers to this question, depending on the destination of the finished product. I'm an author, editor, and formatter, so I use a variety of fonts.

When writing my own novels, I use Arial 14 pitch. It's crystal clear on the screen and my older eyes can see it. Too bad the small Ls look like capital i's.

For submissions to publishers, Shunn format recommends Courier New because all the letters are evenly spaced ("monospaced"), and it's easy to find extra spaces. Shunn also suggests TNR.

Industry standard for publishing is no longer limited to TNR. The font can be selected based on the genre and expected readership, as well as to adjust the number of pages. I've recently used Garamond 11 pitch, Sabon Next LT 11 pitch, and TNR 12 pitch in formatting books. Trim size and topic can also determine font style and size. In a 5 X 8 book, 12 pitch looks too big, and makes it feel like one is reading a children's book, but 11 pitch is scaled for the page. The pitch size is supposedly the number of characters that will fit in an inch of type, but in Word, pitch size actually varies with font, so beware.

I like Calibri, either 10 or 11