Vocabulary lists for most major textbooks. Downloading the lists requires free signup to Skritter. Read more.

skritter.com

This site contains a huge number of lessons, complete with texts, vocabulary, audio, exercises and much more. And it's all free. Note that if you want to get the intermediate and advanced material,... Read more.

collections.uiowa.edu

Outlier Linguistics Dictionary of Chinese characters is an excellent tool to help you understand and thereby learn Chinese characters more effectively. It gives you instant access to the latest res... Read more.

outlier-linguistics.com

HiNative is a Q&A site where you can ask people all over the world about culture, language, anything. We support over 100 languages. Read more.

hinative.com

This website allows you to look up all sorts of things related to characters, including pronunciation in historical and regional varieties, components based on their pictographic origin, and much m... Read more.

zi.tools

This is a digital version of the official authoritative stroke order standard used in China. It is sorted by stroke and is not searchable, so it's a bit hard to use. Thus, other resources will ofte... Read more.

yuke.blcu.edu.cn

Character frequencies for Classical Chinese (i.e. not based on texts). This resource was discussed in this article: [The most common Chinese words, characters and components for language learner... Read more.

lingua.mtsu.edu

Have you ever wondered how names from other languages are transliterated into Chinese? There is actually a reference table where you can see how different sounds are translated into Chinese charact... Read more.

en.wikipedia.org