Luiggi Caldas • September 2, 2026

What Is the Hardest Language to Learn? | Lingua

The Short Answer

For native English speakers, the U.S. Foreign Service Institute places Arabic, Mandarin Chinese, Cantonese, Japanese, and Korean in its most demanding category — roughly 2,200 classroom hours to reach professional working proficiency, about four times what Spanish or French requires. Among these, the FSI singles out Japanese as typically the most difficult.

But that ranking only holds for English speakers. Change the starting point and the ranking changes with it.

Contents

  1. Why "hardest language" is an incomplete question
  2. What the FSI actually measures — and what it doesn't
  3. The FSI categories in full
  4. The hardest languages for English speakers
  5. What makes each one difficult
  6. The hardest languages for Spanish and Portuguese speakers
  7. The hardest languages for Arabic speakers
  8. The hardest languages for Mandarin, Japanese, and Korean speakers
  9. Difficulty is not one thing: the five dimensions
  10. The UNESCO ranking that does not exist
  11. Is English one of the hardest languages?
  12. The easiest languages, by starting point
  13. What actually determines how hard your language will be
  14. Frequently asked questions

1. Why "Hardest Language" Is an Incomplete Question

Ask which language is hardest and you will get an answer — usually Mandarin, Arabic, or Japanese. That answer is not wrong, but it is answering a question that was never fully asked.

The complete question is: hardest for whom?

Consider three learners approaching Mandarin Chinese.

An English speaker faces a writing system with thousands of characters, four contrastive tones, and almost no shared vocabulary. The FSI estimates roughly 2,200 hours.

A Japanese speaker already reads thousands of Chinese characters — kanji were borrowed from Chinese — and shares a substantial portion of Mandarin's Sino-Japanese vocabulary. The writing system, which is the single largest obstacle for the English speaker, is largely already solved.

A Cantonese speaker shares most of the writing system and a related grammatical structure. The tones differ in number and realization, but the concept of contrastive tone is already native.

Same language. Three fundamentally different learning problems.

This is not a technicality. It is the central finding of research on linguistic distance — the measure of how far apart two languages sit in terms of grammar, phonology, vocabulary, and writing system. The greater the distance between your native language and your target, the more time and effort acquisition requires.

Difficulty is not a property of a language. It is a property of the relationship between two languages.

A language is not inherently hard. It is distant.

2. What the FSI Actually Measures — and What It Doesn't

Nearly every article on this topic cites the Foreign Service Institute. Very few explain what the data actually represents, which leads to it being treated as a universal law rather than what it is.

What the FSI is

The FSI is the U.S. Department of State's training institution. For roughly seven decades it has taught foreign languages to American diplomats and foreign service personnel, and it has recorded how long students take to reach a defined proficiency level.

That record is the most reliable dataset of its kind in existence. It is based on observed outcomes, not estimation.

The four limitations you need to know

It measures one direction only. The FSI trains native English speakers. Its categories describe difficulty from English. There is no FSI equivalent measuring difficulty from Spanish, Arabic, or Mandarin — a point the FSI itself does not obscure, but that gets lost in secondhand reporting.

It describes a specific learner profile. FSI students are motivated adults in full-time intensive instruction, professionally selected, with strong support and clear incentives. Someone studying three hours a week around a job is not the population these numbers describe.

It measures a specific target. The hour counts correspond to "Professional Working Proficiency" — roughly ILR Level 3, approximately B2/C1 on the CEFR scale. Not conversational ability. Not fluency in the colloquial sense. A specific, testable professional standard.

It measures speaking and reading. It does not separately quantify writing difficulty, listening comprehension in dialect-heavy environments, or cultural pragmatics.

Why this matters

Citing "2,200 hours" as though it applies to everyone is the most common error in this topic. It applies to a motivated English-speaking adult in full-time intensive training aiming at professional proficiency.

Used correctly, the FSI data is excellent. Used as a universal difficulty law, it is misleading.

3. The FSI Categories in Full

Estimates for native English speakers, to reach Professional Working Proficiency:

Category Hours Weeks Languages
I 600–750 24–30 Spanish, French, Italian, Portuguese, Romanian, Dutch, Norwegian, Swedish, Danish, Afrikaans
II ~900 ~36 German, Haitian Creole, Indonesian, Malay, Swahili
III ~1,100 ~44 Hindi, Russian, Vietnamese, Turkish, Polish, Thai, Serbian, Greek, Hebrew, Finnish, Hungarian, Czech, Ukrainian, Tagalog, Urdu
IV ~2,200 ~88 Arabic, Mandarin Chinese, Cantonese, Japanese, Korean

Note: category numbering has varied across FSI publications; some versions use five categories. The hour estimates are consistent across versions. Verify current classifications at state.gov.

The FSI notes that Japanese is typically more difficult than the other languages in its highest category.

The most useful thing this table shows is not the ranking. It is the magnitude of the gap: the hardest group requires roughly three to four times the hours of the easiest. That is not a matter of degree — it is a different order of commitment.

4. The Hardest Languages for English Speakers

Based on FSI classification, with the caveat that within the top category the ordering is a matter of interpretation rather than measurement.

1. Japanese

The FSI's own note that Japanese is usually harder than its category peers reflects a specific problem: literacy.

Japanese uses three writing systems simultaneously. Hiragana and katakana are syllabaries of 46 characters each and can be learned in weeks. Kanji — characters adapted from Chinese — number in the thousands, and most have multiple readings depending on context.

Japanese grammar is also structurally distant from English: verb-final word order, extensive particle system, and a layered honorific register ( keigo ) in which the same idea is expressed differently depending on social relationship.

The compensation: Japanese pronunciation is comparatively straightforward for English speakers. It is not tonal and has a small phoneme inventory.

2. Mandarin Chinese

Two obstacles, both substantial.

Tone. Mandarin uses four contrastive tones plus a neutral tone. Pitch is not expressive — it is lexical. Change the tone and you change the word, not the emotion. English speakers use pitch for emphasis and emotion, so this requires rewiring a deeply automatic habit.

Characters. Mandarin uses a logographic writing system. Characters generally do not encode pronunciation, so reading and speaking must be learned largely as separate skills. Functional literacy requires memorizing thousands of characters.

The compensation: Mandarin grammar is genuinely simple by comparison. No verb conjugation, no grammatical gender, no plural inflection, no tenses in the European sense.

3. Arabic

Three distinct challenges.

Diglossia. Modern Standard Arabic is the written and formal register, but nobody speaks it as a native language. Spoken Arabic varies enormously by region — Moroccan and Iraqi Arabic are not mutually intelligible in practice. Learning Arabic effectively means learning two things: MSA plus at least one dialect.

Root-and-pattern morphology. Words are built from three-consonant roots modified by vowel patterns. It is elegant and systematic, but it is a fundamentally different word-formation model than English uses.

Script. Right-to-left, letters change shape by position, and short vowels are typically omitted in ordinary text. Readers supply them from knowledge of the word.

4. Korean

Korean's writing system, Hangul , is often described as one of the most logical alphabets ever devised. It can be learned in a matter of hours.

The difficulty lies elsewhere: verb-final word order, an extensive particle system, an elaborate honorific system encoded grammatically rather than lexically, and almost no vocabulary overlap with English apart from recent loanwords.

5. Cantonese

Shares Mandarin's character-based writing system but adds tonal complexity — Cantonese is generally analyzed as having six tones, compared to Mandarin's four. It also has fewer standardized learning resources than Mandarin, which affects difficulty in practice even where it does not affect it in structure.

5. The Hardest Languages for Spanish and Portuguese Speakers

No institution has produced FSI-equivalent hour data for Spanish or Portuguese speakers. What follows is analysis grounded in documented principles of linguistic distance — language family relationship, writing system, phonological inventory, and lexical overlap — not measured hour counts. We are explicit about that distinction because several sites present similar analysis as though it were data.

What gets easier

Spanish and Portuguese speakers hold advantages that English speakers do not.

Other Romance languages — Italian, French, Catalan, Romanian — are substantially closer than they are for English speakers. Shared Latin grammar, shared vocabulary, shared verb systems.

English is easier than most English speakers assume it is for Spanish speakers. Roughly 60% of English vocabulary derives from Latin or French, producing thousands of cognates. English grammar is also simpler in several respects than Spanish grammar: no grammatical gender, minimal verb conjugation, no subjunctive of comparable complexity.

Phonology is a mixed picture. Spanish has five vowel qualities; English has twelve to twenty depending on dialect. Vowel discrimination is a real obstacle. But Spanish speakers face fewer consonant difficulties than speakers of languages with smaller consonant inventories.

What stays hard

The Category IV group — Mandarin, Japanese, Korean, Arabic, Cantonese — remains the hardest tier. Distance from Spanish is comparable to distance from English: unrelated families, unfamiliar scripts, minimal lexical overlap.

What is harder than for English speakers

Germanic languages beyond English. German, Dutch, and the Scandinavian languages are closer to English than to Spanish. An English speaker learning German has structural and lexical footholds that a Spanish speaker does not.

Tonal languages. Neither Spanish nor English is tonal, so this is a shared obstacle — but Spanish speakers have somewhat less experience with pitch-based distinctions than English speakers, who at least use pitch contours for grammatical emphasis.

A specific advantage worth naming

Spanish and Portuguese speakers approaching English arrive with a large passive vocabulary they have not yet activated. Words like information , university , important , possible , and necessary are recognizable on sight. The obstacle is not vocabulary acquisition — it is pronunciation, phrasal verbs, and preposition usage, all of which are learnable in far less time than a vocabulary rebuilt from zero.

6. The Hardest Languages for Arabic Speakers

What gets easier

Hebrew and other Semitic languages. Shared root-and-pattern morphology, related vocabulary, comparable grammatical logic. What is deeply foreign to an English speaker is native architecture to an Arabic speaker.

Persian and Urdu. Not Semitic languages, but both use Arabic-derived scripts and contain substantial Arabic loan vocabulary. The script obstacle largely disappears.

Turkish. Unrelated family, but centuries of contact left significant Arabic vocabulary in Turkish.

What stays hard

European languages present a different problem set than they do for other Europeans. Latin script must be learned. Vowel systems are more elaborate. Grammatical gender and article systems have no direct Arabic parallel in form.

East Asian languages remain maximally distant — different family, different script, different phonology.

The specific obstacle

Arabic speakers learning English typically face difficulty with the /p/–/b/ distinction (Arabic has no /p/), the /v/ sound, consonant clusters, and vowel discrimination — since Modern Standard Arabic has three short and three long vowels against English's twelve to twenty.

7. The Hardest Languages for Mandarin, Japanese, and Korean Speakers

This section demonstrates the central point of this article more clearly than any other.

For Mandarin speakers

Japanese is comparatively accessible — kanji are Chinese characters, and a large body of Sino-Japanese vocabulary is shared. The single largest obstacle facing an English speaker learning Japanese is substantially reduced.

Cantonese and other Chinese varieties share the writing system almost entirely.

European languages are the hard tier. Alphabetic writing, verb conjugation, grammatical gender, articles, plural marking, and tense systems — none of which exist in Mandarin — must all be built from nothing.

For a Mandarin speaker, English is a hard language. Not because English is objectively difficult, but because the distance is large.

For Japanese speakers

Korean is the easiest major foreign language for Japanese speakers, and vice versa. The two share verb-final word order, particle systems, and honorific structures encoded grammatically. Vocabulary differs, but the architecture is familiar.

Mandarin is easier than for Westerners due to shared characters, though the tonal system is entirely new — Japanese has pitch accent but not contrastive lexical tone.

English and European languages rank among the hardest. Japanese learners of English face word order that is nearly the mirror image of their own, article systems that do not exist in Japanese, consonant clusters absent from Japanese phonology, and the /r/–/l/ distinction that Japanese does not encode.

For Korean speakers

The pattern mirrors Japanese. Korean and Japanese are structurally close. English is distant.

The point this makes

For roughly 1.5 billion native speakers of Mandarin, Japanese, and Korean, English is one of the hardest widely-studied languages in the world.

Any ranking that places English in the "easy" tier is answering the question from one direction only.

8. Difficulty Is Not One Thing: The Five Dimensions

Treating difficulty as a single score obscures the most useful information. A language can be brutal in one dimension and simple in another — and knowing which is which tells you what your first year will actually look like.

Writing system

The distance between your script and the target script.

Hardest for Latin-alphabet users: Chinese characters, Japanese kanji.
Moderate: Arabic, Hebrew, Cyrillic, Devanagari, Thai.
Easy: any Latin-alphabet language. Korean Hangul also belongs here despite Korean's overall difficulty — the alphabet is learnable in hours.

Grammatical complexity

Number of grammatical distinctions the language obliges you to mark.

Hardest: Hungarian and Finnish (extensive case systems), Russian and Polish (six or seven cases plus aspect), Arabic (root morphology), Georgian (complex verb agreement).
Simplest: Mandarin, Vietnamese, Indonesian — minimal or no inflection.

Notably, Mandarin has among the simplest grammars of any major language while being among the hardest overall. Grammar is not the bottleneck there.

Phonology

Sounds and sound distinctions absent from your native language.

Hardest for most learners: tonal languages (Mandarin, Cantonese, Vietnamese, Thai), Arabic (pharyngeal and emphatic consonants), Danish (vowel inventory and reduction).
Easiest: Spanish, Japanese, Italian — small phoneme inventories and consistent sound-spelling correspondence.

Lexical distance

How much vocabulary you can recognize before studying it.

For an English speaker, French offers thousands of recognizable words. Mandarin offers essentially none. This dimension alone accounts for a large share of the FSI hour gap.

Availability and exposure

Not a property of the language, but a real factor in acquisition speed.

Spanish learners have unlimited free material, native speakers in most cities, and abundant media. A learner of Georgian or Icelandic has far less, regardless of the language's structural properties.

9. The UNESCO Ranking That Does Not Exist

You will encounter the claim, on multiple sites, that UNESCO has officially ranked the world's languages by difficulty and declared Chinese the hardest.

No such ranking exists.

UNESCO does not rank languages by difficulty. It has never published such a list. The organization's language work concerns endangered languages, mother-tongue education, and linguistic diversity — not difficulty rankings.

The claim appears to originate from a widely-copied internet list, sometimes paired with an equally unfounded assertion that UNESCO ranked languages by "beauty" using consonant-to-vowel ratios. Neither is a recognized linguistic metric, and neither traces back to any UNESCO publication.

We mention this because the claim circulates on pages that otherwise appear authoritative, and because the alternative — real, verifiable FSI data — is readily available and more useful.

When you see "officially ranked by UNESCO," treat the source with caution.

10. Is English One of the Hardest Languages?

Not by most measures — but the answer is more interesting than a simple no.

English grammar is genuinely simple compared to most European languages. No grammatical gender. Minimal verb conjugation. No noun cases. Relatively flexible word order.

English spelling and pronunciation are genuinely difficult. The letter sequence ough is pronounced at least six different ways: through , though , tough , thought , cough , thorough. Sound-spelling correspondence in English is among the least regular of any language using the Latin alphabet.

And crucially: for the roughly 1.5 billion native speakers of Mandarin, Japanese, and Korean, English is one of the hardest widely-studied languages available. Word order inverts. Articles do not exist in their languages. Consonant clusters are unfamiliar. Vocabulary overlap approaches zero.

English is easy for Dutch speakers and hard for Japanese speakers. The same principle governing every other language on this page governs English too.

For a full analysis of what makes English difficult and how long it takes by native language, see Is English Hard to Learn?

11. The Easiest Languages, by Starting Point

If your native language is The most accessible major languages
English Spanish, French, Italian, Portuguese, Dutch, Norwegian, Swedish, Danish, Romanian, Afrikaans
Spanish Portuguese, Italian, Catalan, French, Romanian — then English
Portuguese Spanish, Italian, Catalan, French — then English
French Italian, Spanish, Portuguese, Catalan, Romanian
German Dutch, English, Scandinavian languages
Russian Ukrainian, Belarusian, Polish, Czech, Serbian, Bulgarian
Arabic Hebrew, Maltese, Persian, Urdu
Mandarin Cantonese and other Chinese varieties, Japanese (writing system)
Japanese Korean, then Mandarin (writing system)
Korean Japanese, then Mandarin (writing system)

The pattern is consistent across every row: the closest language is the easiest language. This holds regardless of any language's intrinsic complexity.

12. What Actually Determines How Hard Your Language Will Be

Five factors, in approximate order of impact.

Linguistic distance from your native language. The single largest predictor. Everything else operates within the range this sets.

Any additional languages you already speak. A Spanish speaker who also speaks English approaches German with two sets of footholds instead of one. Multilingual learners consistently acquire additional languages faster — partly from transferable vocabulary, partly from developed metalinguistic awareness.

Your learning environment. Living where the language is spoken produces immersion that no classroom replicates. This can compress timelines substantially — enough to outweigh several categories of structural difficulty.

Your motivation and its specificity. A concrete goal with a deadline outperforms general interest reliably. This is among the best-documented findings in second language acquisition.

Resource availability. Abundant material, accessible instruction, and available conversation partners affect real-world difficulty independently of structural distance.

Note what is absent from this list: talent. Aptitude varies, but it explains far less of the outcome than distance, environment, and consistency.

13. Frequently Asked Questions

What is the hardest language to learn?

There is no single answer, because difficulty depends on your native language. For English speakers, the FSI places Arabic, Mandarin, Cantonese, Japanese, and Korean in the most demanding category at roughly 2,200 hours, with Japanese noted as typically hardest. For Japanese or Korean speakers, English and other European languages rank among the hardest.

Is Mandarin or Arabic harder?

For English speakers, both sit in the FSI's highest category at similar hour estimates. The difficulties differ in kind: Mandarin's obstacles are tone and characters, while its grammar is simple. Arabic's obstacles are diglossia — a formal written register distinct from every spoken dialect — root-and-pattern morphology, and script. Which feels harder depends on the individual learner.

Why is Japanese considered harder than Mandarin by the FSI?

The FSI notes Japanese as typically more difficult than its category peers, largely due to literacy demands. Japanese requires three writing systems simultaneously, and kanji characters carry multiple readings depending on context — a complication Mandarin does not have.

Did UNESCO rank the hardest languages?

No. UNESCO has never published a ranking of languages by difficulty. That claim circulates widely online but does not trace to any UNESCO source. The FSI classification is the credible, verifiable alternative.

How long does it take to learn a hard language?

The FSI estimates approximately 2,200 classroom hours for its most demanding category, for motivated English-speaking adults in full-time intensive training targeting professional working proficiency. Part-time study extends this proportionally.

Is English one of the hardest languages?

By most measures, no — English grammar is simpler than most European languages. But English spelling and pronunciation are genuinely irregular, and for speakers of Mandarin, Japanese, Korean, and Arabic, English is one of the hardest widely-studied languages available.

What is the easiest language to learn?

Whichever is closest to a language you already speak. For English speakers, Category I languages — Spanish, French, Italian, Portuguese, Dutch, and the Scandinavian languages — require roughly 600–750 hours. For Spanish speakers, Portuguese and Italian are more accessible still.

Does the FSI ranking apply to everyone?

No. The FSI trains native English speakers, so its categories describe difficulty from English only. No equivalent dataset exists for other native languages, which is why rankings for Spanish, Arabic, or Mandarin speakers are necessarily reasoned analysis rather than measured data.

Can I learn a Category IV language?

Yes. Thousands of people do every year. The FSI numbers describe how long it takes, not whether it is possible. What the data indicates is the scale of commitment — a hard language is a multi-year project, not a multi-month one.

References

  1. U.S. Department of State, Foreign Service Institute. Foreign Language Training. https://www.state.gov/foreign-language-training/
  2. Council of Europe. Common European Framework of Reference for Languages. https://www.coe.int/en/web/common-european-framework-reference-languages
  3. American Translators Association. What Is the Hardest Foreign Language to Learn? https://www.atanet.org/starting-your-career/what-is-the-hardest-foreign-language-to-learn/
  4. Interagency Language Roundtable. ILR Skill Level Descriptions. https://www.govtilr.org
  5. UNESCO. Languages and Multilingualism. https://www.unesco.org/en/languages-multilingualism

Written by the academic team at Lingua Language Center — ACCET-accredited and SEVP-certified English language school in South Florida. Since 1998 we have taught English and foreign languages to students from more than 60 countries, which informs the native-language analysis in this article.