Vocabulary Coverage Calculator
Estimate reading comprehension from vocabulary size using lexical frequency research.
See your percentage and how many unknown words appear per page of text.
Text Coverage
Lexical Coverage and Comprehension
Research by Paul Nation and others found these coverage thresholds (for native-level everyday text):
| Vocabulary Size | Text Coverage | Comprehension |
|---|---|---|
| 1,000 words | ~75% | Very difficult, many gaps |
| 2,000 words | ~85% | Hard, 1 unknown per 7 words |
| 3,000 words | ~90% | Challenging, 1 unknown per 10 |
| 5,000 words | ~95% | Comfortable, 1 per 20 |
| 8,000 words | ~98% | Near-native reading |
| 10,000+ words | ~99% | Full native-level coverage |
98% coverage is often cited as the minimum needed to read without a dictionary.