"We estimate that 30 000 people attended. We can obviously not count every person's head, but we had an aerial view and our public policing [unit] is well trained in making these estimates," General Sally de Beer told News24.
"It [the number of people who attended] won't be much more or much less."
De Beer said attendance numbers were about the same at the anti-Zuma march to the Union Buildings on Friday. At the time, government estimated that 60 000 people attended anti-Zuma marches nationwide.
De Beer said there were no major incidents on Wednesday.
"The crowds were very peaceful and dispersed in an orderly manner. Overall it was a very good day," she said.
De Beer did however mention that eight people were arrested for the looting of a shop following the march.
On Friday communications Minister Ayanda Dlodlo thanked South Africans for peaceful marches after Acting National police commissioner Khomotso Phahlane on Thursday called the march in Tshwane illegal.
"Today's [Friday's] activities show a strengthening democracy which shapes public discourse," she said.