Vocabulary Learning Calculator
How long it takes to reach a target vocabulary at a daily pace, allowing for the words that do not stick — and the pace needed to get there by a deadline.
Learning a language is largely counting words: a few hundred for survival, a couple of thousand for conversation, several thousand for reading comfortably.
How the vocabulary learning calculator works
Learning a language is largely counting words: a few hundred for survival, a couple of thousand for conversation, several thousand for reading comfortably. Divide the words still to learn by what is actually retained each week — new words a day, times the share that survive review, times study days — and the weeks fall out.
The last row turns it round: the daily pace that reaches the target in twelve weeks.
Formula: retained per week = new words per day × retention × study days per week; weeks = (target − known) ÷ retained per week
Worked examples
| Inputs | Weeks to the target | Note |
|---|---|---|
| Conversational target | 42.4 weeks | 1,800 words at 42.5 a week |
| Every day, twenty words | 15.1 weeks | 119 a week |
| Reading target | 67.9 weeks | 5,500 at 81 a week |
FAQFrequently asked questions
How many words do I need?
Rough thresholds: a few hundred for basic survival, around 1,000–2,000 for everyday conversation, 3,000–5,000 to follow most speech and simple texts, and 8,000 or more to read widely without a dictionary. Frequency lists put the most useful words first, so early words carry the most weight.
What retention rate is realistic?
With spaced repetition, 80–90% of words reviewed on schedule are still known weeks later; without structured review it is far lower. The figure should describe words that remain known, not words that were seen once.
Is ten words a day a good pace?
It is sustainable for most people alongside other study, and at 85% retention five days a week it reaches 2,000 words in about ten months. Twenty a day halves that but doubles the review load, which is where ambitious paces usually fail.
Does a word learned count as a word known?
Recognising a word and being able to use it are different levels, and most counts refer to recognition. If the target is active use — speaking and writing — expect the calendar to stretch, because production takes more repetition than recognition.
Where these figures come from
- Brysbaert (2019), Journal of Memory and Language — How many words do we read per minute? — the 238 wpm silent reading rate, from 190 studies
- Office for Students — the regulator for English higher education
Last checked: September 2026. Reading and writing rates are from published meta-analyses, cited on the page.