This article is about some online resources for HSK learning. It is NOT required or recommended for official course.  Please distinguish these resources carefully by yourself if you need.

DO NOT pay money to any website.

1. http://www.chinesetest.cn/godownload.do

The official website for HSK test. The exam outline and sample exam can be downloaded here.

2.华文慕课 - 中文MOOC平台 (chinesemooc.org)

The free online course of Peking University for HSK 1-3.

Register the account by email and take the online course from the HSK 1.

3. https://www.coursera.org/courses?query=chinese

This website contains different level of Chinese language courses from several Chinese universities. Student can also select the specific direction to study, like Characters or Business Communication.

Register the account by email. If you choose the course without the online certificate, the course will be free. 

4. https://dict.naver.com/linedict/zhendict/dict.html#/cnen/home

Online dictionary for HSK.  Free and no need to register.

5.https://search.bilibili.com/all?keyword=HSK&from_source=webtop_search&spm_id_from=333.1007&search_source=5

Searching the key words like "hsk" in this video website. All videos are free and can be watched without registration. But the quality of these videos varies widely. Please select the video carefully.