Let's trace number of Chinese characters from Han Dynasty 汉朝 (206 B.C. to 220 A.D.)
说文解字 (Shuwenjiezhi) - The first complete dictionary that listed all Chinese character was published in Han Dynasty 汉朝 at around 100 A.D. It was regarded as the origin of Chinese characters. It included 9,353 characters.
康熙字典(Kangxi) - well known classic of Chinese dictionary was published in 1716 of Qing Dynasty 清朝. The Kangxi dictionary included about 46,964 characters compiled in 42 booklets. Most of characters were unused and rare variant accumulated over centuries. Those characters were regrouped under 214 radicals still in use today in many dictionaries to classified characters in traditional form.
The first official simplified form characters were published in 1956 by People's Republic of China. Many additions and modifications to original list were adopted since. The list included 6,500 simplified characters.