Not all languages take the same effort to learn — and the difference is not small. The same learner, studying the same number of hours a week, can expect to reach conversational ability in Spanish in roughly a third of the time it takes to reach the same level in Mandarin or Arabic. Here is why, using the most widely cited framework for language difficulty, and what it means for setting a realistic timeline.
The FSI framework, explained
The US Department of State’s Foreign Service Institute (FSI) has trained American diplomats in foreign languages since the 1950s and, in doing so, has built the most extensively documented record of how long different languages actually take native English speakers to learn to a professional standard. FSI groups languages into categories based on the classroom hours typically needed to reach general professional proficiency (roughly equivalent to a strong CEFR B2/C1), from around 600–750 hours for the closest languages up to 2,200 hours or more for the most distant ones. These figures come from full-time, intensive diplomatic training with highly motivated adult learners, so treat them as a guide to relative difficulty rather than a literal timetable for part-time study.
What actually makes a language harder
Difficulty for an English speaker is driven by a combination of factors, and languages that are difficult for one of these reasons are often difficult for several at once:
- Shared vocabulary (cognates). French, Spanish and Italian share huge amounts of Latin-derived vocabulary with English, so a lot of reading comprehension comes almost for free. Languages with no shared vocabulary base offer no such shortcut.
- Writing system. A language using the Latin alphabet, even with new accents or letters, is far faster to become literate in than one using a logographic system (Chinese characters) or a different script learned from scratch (Arabic, Korean’s Hangul, Russian’s Cyrillic).
- Grammar structure. Case systems, verb conjugation complexity and word order that differs sharply from English all add learning time, independent of vocabulary.
- Sound system. Tonal languages (Mandarin, Cantonese, Vietnamese, Thai) and languages with sounds that do not exist in English require learners to train their ear and mouth to distinguish and produce genuinely new sounds, which takes sustained practice beyond simple vocabulary memorisation.
Roughly where common languages fall
Category boundaries are occasionally revised and different published versions of the FSI list group individual languages slightly differently, so treat the following as broadly representative rather than an exact official table:
- Closest to English (around 600–750 hours): Spanish, French, Italian, Portuguese, Dutch, and other languages that share the Latin alphabet, a large amount of cognate vocabulary and relatively straightforward grammar.
- Moderate distance (around 900 hours): German and similar languages, where grammar (notably case endings and word order) adds real time despite a shared alphabet and many cognates.
- Significant distance (“hard languages”, often 1,100 hours or more): Russian, Greek, Turkish, Finnish, Hebrew, Thai, Vietnamese and others with unfamiliar grammar, a different script, or both.
- Greatest distance (“super-hard languages”, typically 2,200 hours or more): Mandarin, Cantonese, Arabic, Japanese and Korean, which combine an unfamiliar writing system with grammar and, in several cases, a sound system very different from English.
Turning hours into a realistic calendar timeline
The hours only become meaningful once you attach your own weekly study time to them. As a rough illustration:
| Weekly study time | Category I language (~700 hrs) | “Hard” language (~1,100 hrs) | “Super-hard” language (~2,200 hrs) |
|---|---|---|---|
| 3 hours/week | ~4.5 years | ~7 years | ~14 years |
| 8 hours/week (a serious part-time commitment) | ~1.7 years | ~2.6 years | ~5.3 years |
| 25+ hours/week (full-time intensive study) | ~7 months | ~11 months | ~22 months |
These figures assume the hours are FSI’s professional-working-proficiency target, which is a considerably higher bar than “can hold a holiday conversation” — most casual learners reach conversational comfort well before hitting these totals. The table is useful less for the exact numbers and more for the ratio between languages: whatever your realistic weekly hours are, a “super-hard” language will take roughly three times as long as a Category I one to reach the same standard.
FSI hours versus CEFR levels
FSI’s hour bands measure something slightly different from the CEFR-based guided learning hours you will see quoted elsewhere (commonly cited as roughly 180–200 hours to reach CEFR A2, rising to 700–800 hours for C1) — the CEFR figures are generic averages not broken down by target language, while FSI’s are specific to how far each language sits from English. Use CEFR hours as your general planning baseline (see our guide on choosing a course format for how those hours translate into course length), and use the FSI categories above to adjust your expectations up or down depending on which language you are actually learning.
What shortens the timeline in practice
Three things reliably move a learner faster than the average hours above would suggest: sustained immersion (see our guide to what to expect from immersion and study abroad programmes, where research on exchange students shows measurable proficiency gains even after a single term), prior experience with a related language (a Spanish speaker learning Italian or French starts with a considerable head start), and consistent, evidence-based study habits rather than sporadic effort (see our guide to learning techniques backed by research). None of these change the underlying difficulty of the language itself, but they all affect how efficiently the hours convert into actual ability.
Sources: U.S. Department of State, Foreign Service Institute, Foreign Language Training Orientation; Council of Europe, Common European Framework of Reference for Languages (CEFR) level descriptions.
FSI hour estimates are based on full-time, intensive classroom training for adult learners and are intended as a guide to relative difficulty between languages, not a guaranteed timetable for part-time or self-directed study.