Knowledge of 3,000 characters is basic literacy. 4000-5000 is well-educated. HSK tests use about 5000 characters.

Harregarre is almostly right. while HSK has three levels：basic level, middle level, and senior level. and it's different according to the level. well i forget the detail. for chinese, totally about 9 thousand, no more than ten. and about 5 thousand are used in daily life.

据了解，1994年出版的《中华字海》收入了87019个汉字，而已经通过专家鉴定的北京国安咨询设备公司的汉字字库，收入有出处的汉字 91251个，据称是目前全国最全的字库。与庞大的汉字库形成鲜明对照的是，历代日常书面语常用的不同的汉字数量一般都控制在三四千个。数量上并没有超过最初的文字甲骨文。国家在1988年公布的《现代汉语常用字表》选收了2500个常用字、1000个次常用字，总共只有3500字。

Hada and Harregarre are correct but neither of them told you the good news...you only need to master about 1500 characters to be able to converse on a day-to-day basis!!! OK you won't be able to hold a professinonal/technical convo but atleast you'll be able to live and get around without the aid of your friends!

con 400 dominas el lenguaje mas rudimentario necesitas 3 mil para leer letreros comunes y corrientes, y los nombres de las ciudades chinas mas grandes necesitas a partir de 8 mil para leer las noticias, cuentos y poesia clasica