writtenchinese.com
A well-thought design of this dictionary makes the process of learning new characters more efficient by stimulating visual memory. Basic display customization of some components can be very helpful for your personal learning trajectory. A lot of additional information is provided with every search so that it is easier to memorize new vocabulary. Good-quality audio recordings of characters and words are great for pronunciation training.
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You can search not only with characters but with Pinyin and English as well.
Radicals used in a character are listed next to it so that you can better understand its origin and remember it.
Such useful information as measure words and example sentences are provided with every search.
There is an option for customization of a prefered writing system (simplified or traditional) and a dialect (Mandarin or Cantonese).
It is also possible to customize the depiction of phonetical information (tones).
mdbg.net
This dictionary is suitable for Chinese learners who seek a deeper understanding of every character. There are many settings options both for searching and for information display to help you focus on your goals in studying. Moreover, the dictionary offers several tools that automate the process of expanding your vocabulary and memorizing it better.
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There are several ways to look up a word (English, Chinese or Pinyin).
A lot of settings for Chinese learners to display new words in accordance with their goals.
A separate dictionary for single characters if you are interested in studing them in depth.
A very helpful feature for searching characters which contain a specific component.
Great writing animation for every character that you can easily follow in your own practice.
An opportunity to create a custom quiz with your list of words and characters.
purpleculture.net
This web-site contains numerous materials and resources for learning Chinese language. A dictionary is only a part of them. With every search a lot of basic information is displayed as well as some little useful things like HSK level of the character, its synonyms and antonyms. However, the best part is a big number of tools (including free ones) that can make learning easier and more fun.
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A lot of useful information is presented right away with every search.
Example words and example sentences containing needed character are provided as well.
A online instrument to practice your writing skills.
Such a great tool as Practice Sheet Generator allows you to make your own writing practice sheets. You can both practice writing new characters and remembering their stroke order.
An online Flashhcards Generator lets you learn up to 50 words at once. In addition to this there are lots of settings to specify your needs in the learning process.
Once your flashcards set is generated you can start practicing right away online or save it and print it later.