Editorial policy and evidence

FluencyClock helps readers plan language learning. Its calculators and articles are planning aids, not promises about how quickly a particular learner will progress. Kevin Fan is responsible for the site; the author page describes his background without claiming professional teaching or research credentials.

Four kinds of evidence

• Published source data: a claim attributed to an external institution should link to the source and retain its population, endpoint and units. Classroom hours are not automatically total study hours.
• Model estimates: adjustments for study method, existing language knowledge and target level are model assumptions where identified as estimates. A calculated result is not a longitudinal study of learners.
• Product information: a description of a course's advertised format or features is not proof of learning effectiveness. Check the provider's current offer before paying.
• Personal experience: an individual story is not a representative result. A comparison on this site should not be read as a hands-on trial unless it explicitly describes what was used, when and how.

Who the baseline describes

The official training baseline concerns English-speaking US foreign-affairs personnel in an intensive training setting. It is not a universal difficulty ranking for all native languages. In particular, learning Mandarin from English and learning English from Mandarin are not interchangeable directions. Translating the interface into Chinese does not validate a new population model. See the full methodology for source links and assumptions.

AI assistance and limitations

AI tools assist with site development and content editing, including this policy update. Their output is not independent evidence, and an AI-generated explanation or hypothetical example must not be presented as a real learner's testimony or a product trial. This policy does not certify that every existing page has received an independent human fact-check. Readers should follow the cited sources for consequential decisions and report unsupported claims.

Commercial independence

Some course links may earn a commission. The calculator's matching rules do not use commission rates, and free, non-commission options are included. This does not make every recommendation right for every person. Consider the stated limitations and alternatives; the methodology explains the matching rules and the privacy policy explains outbound click records.

Corrections and dates

To request a correction, send the page URL, disputed passage and supporting source to the contact address. Corrections should change the affected text and its update date. An update date is not a claim that every external link or price was rechecked that day. Publication dates, source retrieval dates and page modification dates represent different events.

We do not invent learner results, user reviews or testing histories to fill a page. A useful page should answer a distinct question with evidence and limitations; adding words alone does not make its answer more reliable.