Free online vocabulary learning resources include full-text books, subscription services, and freeware. Here is a survey of some of the free tools we have found for the online vocabulary builder.
Books
There is an old but still useful book called The Century Vocabulary Builder, which is available free on this website.
Freeware
It's not exactly a vocabulary-building tool, but our own free tool, "WordStyler", will check your writing for misused words and phrases and other common writing faults.
Mini-course
A free vocabulary-building mini-course is available from Ultimate Vocabulary. The mini-course comes in 5 parts. A lesson is emailed to you each week for 5 weeks. These mini-courses provide good and useful advice, such as how to expand your vocabulary through elaboration techniques. All you need to do is provide your name and email address at Ultimate Vocabulary.
Screensaver
One of the main strategies for building vocabulary is repetition. Ultimate Vocabulary provides a free screensaver of 50 must-know words. You set the screensaver to 1 of 5 lessons. Each lesson contains a set of 10 words. The aim of the screensaver is to reinforce your new vocabulary while your screen is in standby mode. To get the free screensaver, you need to subscribe to the free mini-courses at Ultimate Vocabulary. (The screensaver was available at the time of writing, but the makers suggest the screensaver might not be available indefinitely.)
Words of the Day
Don't forget the free word of the day available on this site. Other free words of the day are available from:
Games
We have our own free vocabulary game, which we will be improving further. Another free vocabulary game is available from FreeRice. As well as traditional games like these, you can also practice your new vocabulary by contributing a neverending story or a mad lib.
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If you own or know about another free online source for building vocabulary, please contact us so that we may list it here.