A strong vocabulary is essential for any standardized test, and ACT is no different. If you want to score high, there is no way around it, and you would have to learn hundreds of new words. However, learning vocabulary doesn’t have to be tedious and boring.

Thanks to the many excellent resources available today, learning new words for exams is easy. To make you choose the best book, I have compiled a list of the 10 best vocabulary books for the ACT exam.

However, do keep in mind that many of these standardized tests use similar vocabulary, so don’t be thrown off if you see an “SAT” vocabulary book on the list. Many of the well-reputed vocabulary books are often marketed towards SAT students, but the same vocabulary applies to ACT.

I will also list some free mobile apps that can be used anywhere without carrying a book.

10. Gruber’s Word Master for Standardized Tests

Gruber’s Word Master is an excellent resource for learning new words for the standardized Test. This book can be used for the ACT, SAT, and GRE. It offers the most frequent 291 words that appear on standardized tests.

Key Features:

• The most important words used on all standardized tests  
• Prefixes and roots that denote the same meaning or feeling
• Commonly confused words
• The 291 most frequent test words
• 50 vocabulary tests with answers
• Prefixes and Roots that decode more than 200,000 words on tests

Get it here.

9. Visualize Your Vocabulary

“Visualize Your Vocabulary” takes a visual approach to learning new words for the ACT and SAT. It is no secret that most people are visual learners, and hence applying the same system to learning vocabulary works way better than mere rote and recitation. This book offers expressive cartoons that stay in your mind and uses them to deliver word meanings.

Key Features:

• 250 illustrations help you retain meanings of 250 most common SAT and ACT words.
• Over-the-top and silly cartoons help you keep new words effortlessly.
• The words are handpicked and are some of the most high-frequency words to show up on the SAT and ACT.
• It can be used for both the SAT and ACT exams.

Get it here.

8. Vocabulary Power Plus Classic for ACT

Bought by millions of students worldwide, this neat little vocabulary book is perfect for learning ACT words. It is also an excellent option for SAT students or anyone else looking to improve their vocabulary skills.

Key Features:

• over 200-word meanings.
• Ideal for SAT and ACT exams.
• Pronunciation Guide.
• Strategies for completing the various activities.

Get it here.

7. Vocabulary for SAT (App)

This neat little Android app is a perfect companion for when you are out and about. It features some 4000 words that will be more than enough for your ACT prep. It is free and straightforward to use.

Key Features:

• 4000+ SAT words list with definition and examples
• Multiple Test on 800 High-frequency words
• High-frequency words are added to the favorite word list.
• Synonyms, Antonyms, One Word Substitutions
• Idioms and Phrases.
• After each Test, the summary will be displayed, indicating your marks and percentage.

Get it here for Android.

6. Direct Hits Core Vocabulary for SAT and ACT

Direct Hit’s Core Vocabulary uses vivid and memorable examples from pop culture, literature, and historical events to give you a deeper understanding of words and their context. This sort of approach works more effectively than simple memorization.

Key Features:

• Selective vocabulary found on recent PSATs, ACTs, and SATs used in context. No more memorizing the definitions of long lists of seemingly random words in a vacuum
• Relevant, vivid, and memorable examples from literature, historical events, contemporary issues, and pop culture
• A Fast Review for each chapter, with quick definitions
• Use of rhetorical and literal devices for better retention.

Get it here. 

5. New SAT Vocabulary (App)

This app contains over 1000 most common SAT words ordered by difficulty level, i.e., Pre-beginner to advanced. However, don’t be confused by the name; even though it says “SAT” in the title, the words included in the app correctly apply to ACT as well. Moreover, the app employs a game-based learning method that makes learning new words amusing and easy.

Key Features:

• A resourceful vocabulary of over 1000 SAT words frequently asked on the real Test.
• Four gaming formats: Multiple choice, Matching, Spelling, and True/ False, scientifically proven to aid the learning of new words.
• Scheduled daily word reviews based on your practice results to optimize memorization.
• Statistical analysis of your progress to help you target and drill your weaknesses.
• Illustrative image for every word to enhance your absorption.

Get it here for Android.

4. Words You Should Know in High School

This book features the most essential 1000 words that appear on the SAT and ACT. Synonyms and antonyms follow words. You will also learn a list of the most commonly misused words.

Key Features:

• Understand commonly misused words
• Learn popular definitions used in standardized tests
• Recognize the difference between synonyms and antonyms
• Perfect spelling and grammar usage
• Choose the right word for every unique course and circumstance

Get it here

3. SAT Flashcards: Prep & Vocabulary by Magoosh (App)

This is an excellent app by Magoosh to learn vocabulary for the SAT and ACT. The app has a clutter-free and intuitive UI that makes navigation easy. There are a total of 350 words that are handpicked by experts.

Key Features:

• 350 vocab words picked by an expert SAT tutor.
• Definitions and example sentences for every concept and word.
• Decks for every difficulty level.
• Track your progress as you study.
• The smart algorithm focuses on your practice for efficient learning.

Get it here for Android.

Get it here for iOS.  

2. Merriam-Webster’s Vocabulary Builder 

This book is an all-time best seller and is used by millions of students worldwide to prepare for ACT, SAT, and GRE. It provides some 3500 most essential words that are likely to show up on standardized tests.

Key Features:

• Organized by 250 Greek and Latin roots as the building blocks for words, this book will aid in learning 1,200 words while introducing 2,000 more words.
• More than 250 new words and roots have been added in this latest edition.
• Includes quizzes after each root discussion to test progress.
• Ideal for GRE, SAT, AND ACT.

Get it here.

1. The Vocabulary Builder Workbook by Magoosh

This is by far the most popular and highly rated book. The Vocabulary Builder by Magoosh orders words by common themes and helps you understand roots and form associations between words. This thematic approach is efficient and, if used correctly, will help you retain meanings for longer.

Key Features:

• A total of 1400 must-know words for SAT, ACT, and GRE.
• Fun and Easy Lessons organized by theme to help you identify roots and form associations, and recognize thousands of additional vocabulary words.
• Progressive Learning Techniques for all levels with vocabulary lessons that steadily increase in difficulty for continued advancement.
• Retention Focused Activities to make sure you remember every word long after the Test is over.

Get it here.