Hexagon paper, half-inch
Hexes a quarter inch from centre to corner — half an inch corner to corner, and about 0.43 inches across the flats.
Opens with these settings already loaded. Change anything you like, then download as PDF, PNG or SVG.
Sized for 15 mm figures
The size control sets the circumradius, so a quarter inch here produces a hex that comfortably holds a 15 mm figure on a small base. That is the usual scale for historical wargaming, where unit counts run high and one-inch hexes would put half the battle off the edge of the table. For 25 to 28 mm figures you want roughly twice this.
More hexes, and therefore more map
A Letter sheet at this size carries about 19 hexes across and 25 down — some 475 on a page, against roughly 120 at one inch. That is the difference between a map of a single skirmish and a map of the whole engagement, and it is close to the scale the classic printed hex wargames used for exactly that reason.
Number the hexes before you draw
Once a map has several hundred cells you need coordinates. The convention inherited from Avalon Hill is a four-digit reference: two digits for the column and two for the row, so 0715 is column seven, row fifteen. Write the column numbers along the top edge and the row numbers down the side before you start adding terrain — retrofitting them onto a finished map is miserable work.
Printing it accurately
This only measures correctly if your printer doesn't rescale the page. In the print dialog set Scale: 100% — not "Fit to page" or "Shrink oversized pages". If you're not sure it worked, print the calibration page, measure the ruler on it with a real ruler, and it will tell you exactly what your printer is doing to the page.