John Gill Commentary Joshua 8:25

"And all that fell that day, both of men and women, were twelve thousand, even all the men of Ai." — Joshua 8:25 (ASV)

And [so] it was, [that] all that fell that day
Partly in the city, and partly in the field, both by the ambush and the army: both of men and women;

[were] twelve thousand, [even] all the men of Ai ;
so that the city was not a very large one, and the numbers of inhabitants were comparatively but few, as in (Joshua 7:3) .