Easy to size up or down, this is sized for a large adult

2 stitches and 1 row = 2.5 cm in One row by 2 stitchs of the hat section is 1x1 inch

Patter has a chart and written instructions.

Uses BLO sc for the brim. The body of the hat is worked all in FPDC with some cable working that gets tricky around row 8 so its not a pattern for someone new to working around the front post.