Language Learning Calculators
Free language learning calculators.
Time to fluency, vocabulary size, study plans, and progress tracking.
Comprehensible Input Calculator
Calculate how many hours of comprehensible input you need to reach fluency. Based on i+1 theory and real acquisition research.
Study Hours to Fluency Calculator
Calculate how long it will take to reach fluency in a foreign language. Based on FSI difficulty ratings and your daily study hours.
Vocabulary Size Estimate Calculator
Estimate your vocabulary size in a foreign language based on a simple test score. See how your word count compares to conversational, fluent, and native benchmarks.