There is no official ILR-to-CEFR conversion table
Every hours-to-CEFR figure on the internet passes through a conversion that no standards body ever published. Published academic tables disagree by a full level. Here is which reading we take and why it makes our numbers larger.
The Foreign Service Institute publishes hours to ILR 3. Almost every learner thinks in CEFR — A1 through C2. So every "600 hours to B2" figure you have ever read, including on this site, has passed through a conversion between the two scales.
No standards body has ever published that conversion.
Two scales that were never designed to meet
The Interagency Language Roundtable scale is a US federal instrument, 0 to 5, built to describe what a government employee can do in a posting. The Common European Framework of Reference is a Council of Europe instrument, A1 to C2, built to describe what a learner can do and to make qualifications comparable across European countries.
Different origins, different purposes, different decades. Neither body has issued a crosswalk to the other, and neither has endorsed anyone else's.
What exists instead is a set of academic and institutional attempts, and they do not agree:
- Some published tables place ILR 3 / 3+ at C1
- Others place C1 nearer ILR 4
That is a full CEFR level of disagreement, at exactly the point where FSI's headline figure sits.
Why a level of ambiguity is a lot
Our own model, Spanish, one hour a day with a tutor:
| Target | Hours |
|---|---|
| B2 | 460 |
| C1 | 630 |
Choosing the wrong end of the disagreement moves an estimate by more than a third — before any question about your method, your background, or your consistency.
Every site quoting FSI hours in CEFR terms has made this choice. Most have made it without noticing there was one.
Which reading we take, and the direction of the error
We treat FSI's 600 hours of Spanish as reaching C1.
That is the lower reading — the one that says ILR 3 corresponds to C1 rather than to something below it. And it makes our estimates larger, because it means C1 costs the full FSI figure rather than a fraction of it.
Two reasons for taking the conservative side:
An overestimate fails safely. Someone who budgets 630 hours and needs 500 has a pleasant surprise. Someone who budgets 400 and needs 630 abandons the language and concludes they are bad at languages.
The commercial incentive runs the other way. A site funded by course referrals benefits from small, encouraging numbers — they make products look more capable. Taking the reading that inflates our own figures is the cheapest possible way to demonstrate the matching rules are not tuned for conversion. How this site is paid for sets out the rest.
The general lesson
The chain behind "X hours to B2" for any language, on any site, is:
- FSI's published hours to ILR 3 — solid
- ILR 3 → CEFR level — no official source, disputed by a full level
- CEFR level → your target level — derived from exam-preparation hour bands
- Adjusted for method and background — estimated coefficients
Step 1 is the only one with an unambiguous published source. Steps 2 through 4 are interpretation, and a page that presents the output as a fact has quietly dropped three layers of it.
We mark all of them. Every estimate here carries its caveats, and the methodology page names each factor, its source, and its confidence — including the ones labelled as estimates, which is most of them below step 1.
Sources
Every figure above, and where it came from. A post that traces other people's unsourced numbers does not get to have any of its own.
- Foreign Language Training — US Department of State, Foreign Service Institute
The class-hour bands every estimate on this site starts from, and the definition of the proficiency they lead to (ILR Speaking-3 / Reading-3).
- 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.
- Guided learning hours — Cambridge English
The shape of the curve between CEFR levels. Cambridge publishes cumulative hours per level (A2 180–200, B1 350–400, B2 500–600, C1 700–800, C2 1,000–1,200); our level factors are normalised against the C1 band and every one lands inside its published range.