How similar are two languages?

How is the similarity score calculated?

The score blends four dimensions: shared vocabulary (40%), grammar structure like cases, genders and word order (30%), writing system (15%) and sound system (15%). Vocabulary uses documented lexical similarity coefficients where they exist (for example Spanish-Portuguese at 89%), and language family distance otherwise.

What are the most similar major languages?

Among widely learned languages: Norwegian and Danish, Czech and Slovak, Croatian and Serbian, Indonesian and Malay, and Spanish and Portuguese are all so close that speakers can often understand each other without studying.

Does knowing a similar language really make learning faster?

Yes, dramatically. Shared vocabulary means thousands of words come for free, and familiar grammar patterns transfer. A Spanish speaker typically reaches conversational Portuguese several times faster than someone starting from zero.

Can two languages be similar without being related?

They can share features without sharing ancestry. Maltese is Semitic but written in the Latin alphabet with heavy Italian vocabulary. Japanese and Korean share grammar logic (SOV order, agglutination) despite no proven family link. The tool scores these overlaps too.

Is 100% similarity possible?

No two distinct languages score 100. Pairs like Croatian, Bosnian and Serbian come closest: they form one dialect continuum and are mutually intelligible, differing mainly in script, vocabulary preferences and small grammar details.

What is the closest language to English?

Among major languages, Dutch is the closest relative of English, followed by the Scandinavian languages (Norwegian, Swedish, Danish) and German. Frisian, a smaller language spoken in the Netherlands, is technically the closest of all.

What is the closest language to Spanish?

Portuguese, with roughly 89% lexical similarity, followed closely by Catalan and Italian. A Spanish speaker can often read Portuguese comfortably from day one, even though the pronunciation takes some ear training.

Are Japanese and Korean related?

No proven family relationship exists, yet they share striking structural similarities: subject-object-verb order, agglutinative grammar, particles and honorific systems. Vocabulary is where they differ most, apart from words both borrowed from Chinese.

Are Chinese and Japanese similar?

Less than people assume. They belong to different families: Chinese is tonal with an isolating grammar, Japanese is non-tonal with rich verb conjugation. What they share is writing: Japanese kanji are Chinese characters, and many Japanese words were borrowed from Chinese centuries ago.

Are Hindi and Urdu the same language?

Spoken casually, they are close to one language (Hindustani): speakers understand each other in everyday conversation. They diverge in writing (Devanagari vs the Perso-Arabic script) and in formal vocabulary, where Hindi draws on Sanskrit and Urdu on Persian and Arabic.

Can Norwegians, Swedes and Danes understand each other?

Largely yes. The three mainland Scandinavian languages are mutually intelligible to a high degree, with Norwegian sitting in the middle: Norwegians tend to understand both neighbours best. Spoken Danish is usually the hardest to parse.

Is it easier to learn a third language than a second?

Usually, yes. You already know how to study, what works for your memory, and you can anchor new vocabulary to two systems instead of one. If the third language is similar to one you speak, the discount is even larger.

Should I learn two similar languages at the same time?

It works if you keep them separated: different study times, different contexts, and above all separate sets of real sentences with native audio so your ear files them apart. Many learners prefer a 6-12 month head start on one before adding its sibling.

What does mutual intelligibility mean?

Two languages are mutually intelligible when speakers understand each other without studying: Czech and Slovak, Croatian and Serbian, Indonesian and Malay. High lexical similarity plus shared grammar usually predicts it, though pronunciation can break it (as with written vs spoken Danish for Swedes).

Which language family is the largest?

By number of speakers, Indo-European dominates: it covers the Romance, Germanic, Slavic, Baltic, Hellenic, Albanian and Indo-Iranian branches, from Spanish and English to Hindi and Persian. Roughly half of humanity speaks an Indo-European language natively.