How much comprehensible input per week yields measurable progress
The amount of comprehensible input per week that yields measurable progress varies with individual learning pace and current proficiency level, but research and anecdotal reports suggest consistent exposure is key. Effective progress tends to emerge when learners engage with input that they mostly understand (Krashen’s “i + 1” principle) regularly over weeks or months. Some learners report measurable progress with hundreds of hours and hundreds of thousands of words read or listened to over longer time frames, while shorter weekly inputs focused on quality and slightly challenging materials also advance skills stepwise.
Key points from research and learner experience:
- Comprehensible input should be slightly above current ability but understandable (i+1).
- Consistent weekly engagement for several hours (e.g., 5+ hours per week) including reading, listening, and watching content in the target language.
- Progress measurement can be made in terms of improved comprehension, vocabulary acquisition, and ability to produce language.
- Tracking input (hours, words) and self-assessment quarterly or monthly helps monitor progress and adjust learning plans.
- Over time, progress is shown by moving through increasingly difficult material and spontaneous use of language.
Based on these insights, a practical recommendation is to aim for at least several hours (around 5 to 10 hours) of quality comprehensible input weekly to see measurable progress, adjusting as proficiency improves and input level rises accordingly. Tracking and reflecting on progress every month or quarter can enhance effectiveness and motivation.
This approach aligns with Stephen Krashen’s language acquisition theory and observed learner practices. 1, 2, 3, 4, 5, 6