A family of Microsoft word processing software products for creating web, email, and print documents.
This is set in the Style for your text. Assuming you are using Normal style, follow these steps:
- In Word, right-click on Normal in Home>Style Gallery and choose Modify.
- In the bottom left corner, click on Format, then Font.
(Note to other readers, you must have both a Western and Asian language enabled to follow this step.) At the top of the Font dialog is the Latin text section. This controls the font size for English. Below it is the Complex scripts section that controls the Thai font. Change the font size to be the same for both sections and OK out.