What is a language you already speak worth?
Research documents cross-linguistic influence. This tool applies our disclosed pair coefficients to estimate a planning discount in hours, and reports zero when the model assigns none.
Where these discounts come from
An empirical third-language study found cross-linguistic influence and reported structural similarity as more predictive than broad typological proximity in its tasks. It supplies no hours-saved coefficient for our pairs. The discounts here are explicit model assumptions: shared branch gets the largest reduction, shared script a smaller one, and the total is capped.
The full model, and every factor it applies: how this is calculated.
How this is worked out
The model looks at how your languages relate to the target across four channels: a shared branch, a shared family, a shared script, and typological similarity between languages that are unrelated by descent. Each contributes a discount, and the total is capped so stacking several known languages cannot produce an implausible result.
It then runs the estimate twice — once with what you speak, once from English alone — and reports the difference in hours. Hours rather than a percentage, deliberately: "8% faster" sounds like a reason to choose a language, and "about 40 hours off a 500-hour project" sounds like what it is.
It reports zero, and zero is the point
Ask what Spanish does for Japanese and this model returns zero. A tool that always finds an encouraging number is not modelling a bounded relationship, and the estimated 30% for Spanish to Portuguese only has meaning because Spanish to Japanese comes back empty.
Every tool here can decline to answer, and that is the most useful thing they do.
Common questions
- I studied a language for years and it says zero. Is that right?
- If the pair is unrelated, yes. What transfers between unrelated languages is the skill of having learned one — study habits, tolerance for ambiguity, knowing what a case or an aspect is — and that is genuinely valuable and does not convert into hours. The model prices linguistic relatedness, which is a narrower thing than experience.
- Why do Japanese and Korean get a discount when they are unrelated?
- Because relatedness by descent is not the only plausible source of transfer. Japanese and Korean share structural features — verb-final order, particles marking grammatical role, elaborate honorific systems — and a learner of one meets familiar machinery in the other. Research supports structural similarity as a factor in cross-linguistic influence; this model’s hour discount for the pair is our estimate, not a published coefficient.
- Can I enter a language I only half-speak?
- The model assumes B1 or above in what you list, because that is roughly where a language is internalised enough to transfer. Listing something you studied for a term will overstate your head start. If you are unsure, leave it out — the estimate errs upward, which fails more safely than the alternative.
Sources
Everything this tool rests on. The current NFATC programme baseline is printed or transparently derived from the same page; the factors applied on top are ours and are marked as estimates.
- Foreign Language Training — US Department of State, National Foreign Affairs Training Center
The current NFATC training timelines: a typical week is 23 class hours plus 17 hours of self-study, aimed at an integrated ILR 3 in Speaking and Listening. Category I lists 24–30 weeks; using the page's typical class week, this site derives 552–690 class hours. Categories II–IV print 828, 1,012 and 2,200.
- 3 FAM 3910 — Language Incentive Pay Program — US Department of State, Foreign Affairs Manual
The separate current S-3/R-3 normal-course table: Spanish is 24 weeks, French 30, Category II 36, Category III 44 and Category IV 88. Its endpoint differs from the current NFATC integrated Speaking + Listening score, so the two tables must not be merged.
- Guided learning hours — Cambridge English
The cumulative shape between CEFR levels. Cambridge publishes guided-learning-hour bands for its English qualifications (A2 180–200, B1 350–400, B2 500–600, C1 700–800, C2 1,000–1,200). Our factors are normalised against C1 rather than fitted to every band; for example, 0.27 × the 750-hour C1 midpoint is 202.5, just above the A2 band.
- ILR scale — Wikipedia
That no official ILR-to-CEFR crosswalk exists. Published academic tables place ILR 3/3+ at C1; others put C1 nearer ILR 4. We take the lower reading, which makes our estimates the more conservative of the two.
- Zhongwen Shuiping Kaoshi (HSK) — Wikipedia
That Hanban's claimed one-to-one HSK-to-CEFR equivalence was rejected by CEFR bodies and is disputed by the German and French associations of Chinese-language teachers, who place old HSK 6 nearer B2–C1 than C2.
- The effect of previously acquired languages on third language acquisition — Heliyon 10(4), original research (2024)
Empirical evidence that previously acquired languages can influence third-language processing, and that structural similarity mattered more than broad typological proximity in the tested tasks. It does not publish an hours-saved coefficient for any pair, so it supports the existence and complexity of transfer but not this site's 30% estimate.
This tool is free and carries no ads or affiliate links. It is funded by commission on some course links elsewhere on the site — which pages, and how that is kept out of the recommendations.
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