The によって Compound Particle: By Means of, Depending on
The によって compound particle is a formal Japanese case marker. It fuses the case particle に with the て-form of 因る ("to be based on") and carries five readings: means, cause, agent in passive sentences, variation source, and conditional basis.12 If you recognise all five readings, plus the sibling forms による, により, and によると, you can read much more news, academic, legal, and business Japanese.34
Overview
によって belongs to the 複合格助詞 family: multi-word units that have lexicalised into a single particle and act as case markers in formal prose.1 The same family includes として, について, に関して, に対して, and をもって. That places によって beside the topic-marker compound particles learners often meet with it at JLPT N3.1
This article sorts the five readings of によって, fixes the morphology of its sibling forms (による, により, によると, によれば, によっては), and compares its register with で, に, より, and the topic compounds.
What "compound particle" means here
A 複合格助詞 (compound case particle) is a fixed combination of a case particle and a verbal element that has frozen into a single grammatical unit. によって is built from に plus the て-form of 因る (yoru), a godan verb meaning "to be based on, to be caused by, to depend on."12
NINJAL (the National Institute for Japanese Language and Linguistics) workshop materials classify によって inside the broader 格助詞性複合辞 ("case-particle-type compound particles") class, alongside として, について, をはじめ, and をもって.1
Because the core verb 因る means "to be based on," the family inherits one semantic core ("X is the basis") and branches outward.56
JLPT level and frequency
JLPT N3 grammar lists group によって, による, により, and によると together. An N3 candidate is expected to recognise all four surface forms in reading.78 N2 reinforcement focuses on the formal による attributive form and the written-formal twin により in business, legal, and academic prose.34
News writing, academic prose, government documents, business email, and contract clauses use the family heavily.34 Spoken Japanese leans on で or から in equivalent slots, so によって in casual conversation reads as stiff or self-important.3
Where it sits next to で, より, について, にとって
で is the neutral colloquial means or instrument particle (バスで行く, "go by bus"). によって is its formal twin, especially for non-physical methods like negotiation, election, or investigation.5 The で particle and the に particle each have their own article in the particles index; you can cross-reference them for the case-particle baselines.
より means "than" in comparisons and can mean formal "by" in some legal contexts. It does not cover cause, agent, or variation.6
にとって marks "from X's perspective" (subjective evaluation), the opposite logical role from によって's objective basis. This article gives only the high-level contrast; see the にとって compound particle article for the deeper sort.
The topic-marker compound particles について, に関して, and に対して share the N + に___ surface frame with によって. But they mark a speech topic or directional target, not a basis. The について article covers the speech-topic baseline, the に関して article covers its written-formal twin, and the に対して article covers the directional target reading.
Form and conjugation
Attachment rule: Noun + によって
The base pattern is Noun + によって + clause.78 によって attaches directly to a noun. It does not attach to a verb stem or to a な-adjective stem, and no の linker comes between the noun and によって.7
A verb phrase can enter the frame only after it has been nominalised, or turned into a noun-like unit. The report frame accepts V + ところ + によると to embed a clause:9
調査したところによると、原因は不注意だ。
"According to the investigation that was carried out, the cause was carelessness."
The five surface forms
The によって family appears in five shapes. Each one fills a different syntactic slot and has its own register.
| Form | Slot | Register | Source |
|---|---|---|---|
| によって | mid-sentence "by / depending on / due to" | formal; spoken-acceptable in careful register | 785 |
| による | attributive: N1 + による + N2 (modifies the following noun) | formal noun modifier | 106 |
| により | mid-sentence twin of によって, almost always before a comma | written-formal: news, legal, business, academic | 34 |
| によると / によれば | sentence-initial "according to" report frame | both written and spoken | 9 |
| によっては | scope-narrowed "in some cases, depending on X" | formal mid-sentence | 711 |
によると conveys higher reliability than によれば; によると is more common in conversation, while によれば appears more in writing.9
による is the only acceptable attributive form for the cause, agent, and basis readings (火災による被害, "damage from a fire"; テロリストによるもの, "something done by terrorists").510
What never inflects
The て-form 因って is frozen inside this compound particle. Do not inflect 因る into 因った or 因りません as an active verb in the によって frame.2
The kanji 因 is JLPT N3-listed (on'yomi イン, kun'yomi よ.る) and appears in compounds such as 原因 ("cause") and 因果 ("cause and effect"). But in the compound particle, the kana forms によって, による, and により dominate.512 The kanji spelling 因って is rare outside legal or academic text.
The five readings, sorted
Reading 1: Means (手段)
The first reading is "by means of X," the formal-register twin of で. It marks non-physical means and abstract instruments: negotiation, vote, investigation, deliberation.5611
Diagnostic: you can replace it with で in casual speech. But で feels too colloquial when the means is a deliberation, institution, or written process.5
調査によって新たな事実が明らかになった。7
"A new fact was brought to light through the investigation."
話し合いによって問題を解決する。5
"We resolve the problem through discussion."
インターネットによる世界のニュースを知る。5
"I learn the world's news through the internet."
In speech, で carries the same load; using によって in casual conversation reads as stiff.34
Reading 2: Cause (原因)
The second reading is "due to X" or "caused by X." The noun in front of によって typically names a natural, institutional, or impersonal event.57
Diagnostic: it pairs with consequence verbs (倒れる, "fall"; 中止になる, "be cancelled"; 遅れる, "be delayed") in past tense, and the cause is usually unwilled.7
大雪によって、電車は二時間以上も遅れました。8
"Due to the heavy snow, the train was over two hours late."
地震によって多くの建物が倒れた。5
"Many buildings fell because of the earthquake."
火災による被害は甚大だった。10
"The damage from the fire was enormous."
In newspaper headlines, the cause reading often appears as により: 台風により被害, "damage due to the typhoon."4
Reading 3: Agent in passive sentences (受身の動作主)
The third reading marks the agent in formal passive sentences. It is the default agent marker when the agent is a creator (author, architect, scientist, or institution) and the patient is a creative, scientific, or institutional work.13145
Diagnostic: the active counterpart's subject is a creator-class agent. The predicate is a creation, discovery, founding, election, invention, or institution verb (書く, "write"; 作る, "make"; 発明する, "invent"; 建てる, "build"; 創立する, "found").1314
この歌は秋元さんによって書かれた。13
"This song was written by Mr. Akimoto."
田中さんによって岡田さんに手紙が送られました。5
"A letter was sent to Mr. Okada by Mr. Tanaka."
電灯の発明はエジソンによるとされている。5
"The invention of the electric light is attributed to Edison."
The に passive-agent slot still exists. It is reserved for personal-experience and adversative ("迷惑の受身," nuisance passive) readings.13 The passive voice article explains the full に / によって split for the agent role.
For now, the cleanest test is the verb class: if the predicate is a creation, discovery, or institutional verb, the agent takes によって.
If you write 『源氏物語』は紫式部に書かれた, you have produced the wrong sentence: the に reads as "for" (beneficiary), not "by" (agent).13 The correct form uses によって to mark a creator-class agent.
For institutional or abstract agents (governments, laws, historical events), によって is the formal default.14
Reading 4: Variation source (〜によって違う / 変わる)
The fourth reading is "it varies depending on X." This is the depending-on reading.87
Diagnostic: the predicate is a difference, change, or variation verb (違う, "differ"; 変わる, "change"; 異なる, "differ"; 決まる, "be decided").8
人によって考え方が違う。8
"Ways of thinking differ from person to person."
国によって、いろいろな伝統があります。7
"Different countries have different traditions."
その車の値段によって、決めます。7
"I will decide depending on the price of that car."
Sentence-final 〜は人による ("it depends on the person") is one of the few casual-register uses that native speakers readily use in speech.7
Reading 5: Basis or condition for an outcome
The fifth reading is "depending on X (it may or may not)." It is often realised as によっては, with は narrowing the scope.711
Diagnostic: the second clause is conditional or hedged, often with かもしれない, ことがある, or a conditional consequence verb (延期する, "postpone"; 中止する, "cancel").511
天候によっては中止もありえるでしょう。5
"Depending on the weather, cancellation is also a possibility."
天気によっては延期します。11
"Depending on the weather, we will postpone (it)."
場合によっては、お返事できないこともございます。11
"Depending on the case, there are times when we are unable to reply."
によっては foregrounds "in some (but not all) cases." If you drop the は, you lose the contrastive scope and the sentence reads as a flat variation statement.11
The related forms
によると / によれば: the according-to frame
によると and によれば form the hearsay or report frame. The source of information appears near the start of the sentence, and the predicate is hedged or reported.9
The pattern is Noun + によると / によれば, or V + ところ + によると / によれば.9 The closing predicate normally pairs with そうだ, らしい, とのことだ, ということだ, or という.9
によると signals higher source reliability and is common in news writing. によれば is slightly softer and appears more in formal writing or literary register.9
天気予報によると、明日は晴れです。9
"According to the weather forecast, tomorrow will be sunny."
警察によると、犯人が逃げたそうです。9
"According to the police, the criminal escaped."
目撃者によれば、犯人は二十代の男性だ。9
"According to the eyewitness, the criminal is a man in his twenties."
The required hearsay or reported ending is the diagnostic that separates によると from the other family members. If the predicate is bare (no そうだ, らしい, or という), the sentence is broken.9
による as a noun-modifier
When によって would link to a following noun, it becomes による. The pattern is N1 + による + N2, meaning "N2 caused by / by / based on N1."610
The attributive form is the only grammatical choice for cause, agent, and basis readings when modifying a noun: 火災による被害 ("damage from a fire"), 不注意によるミス ("mistakes caused by carelessness"), 法律による制限 ("restrictions by law"), 紫式部による小説 ("a novel by Murasaki Shikibu"), 事故による遅延 ("delay caused by an accident").106
When the modified noun is omitted, もの fills the slot: この事件はテロリストによるものだ ("This incident is one caused by terrorists").5
不注意によるミスが多い。10
"Mistakes caused by carelessness are common."
法律による制限がある。10
"There are restrictions imposed by law."
この事件はテロリストによるものだ。5
"This incident is the work of terrorists."
If you drop the second noun, the phrase no longer stands: 火災による on its own is ungrammatical without either a noun or もの.105
により as the written-formal twin
により is the written-formal twin of によって. It is common in news headlines, legal notices, business letters, government documents, and academic prose, and it almost always sits before a Japanese comma (、).34
Spoken Japanese avoids により. Reading the form aloud already marks the speaker as quoting or being formal.3 Newspaper Japanese uses 〜により with the cause and means readings: 台風により被害 ("damage due to a typhoon"), 法改正により ("due to a legal revision").4
台風により、多数の便が欠航となった。4
"Due to the typhoon, many flights were cancelled."
法律により処罰される。3
"Offenders will be punished according to the law."
火災報知器の故障により、避難訓練を中止します。3
"Owing to a malfunction of the fire alarm, we are cancelling the evacuation drill."
によっては: scope-restricting "in some cases"
The topic particle は narrows the scope of the variation reading: "depending on X specifically, it may be different in some cases."117
によっては pairs with かもしれない, ことがある, ことも(ござい)ます, or a conditional consequence in the second clause.11 It belongs to the conditional family alongside 次第で, に応じて, を問わず, and にかかわらず.11
The contrast with bare によって is sharp: 人によって違う states "it varies by person"; 人によっては違う marks "for some people in particular, it differs."11
Nuance and usage contexts
Register: where によって is required vs. preferred
によって is required or strongly preferred in news writing, academic prose, government documents, business email, contract clauses, and formal speeches.34
It is discouraged in casual conversation. In speech, で carries the means load and から carries the cause load, and によって reads as self-important.3
により is the next step up the formality ladder. It is comma-flagged, common in newspapers and legal text, and uncommon in speech.34
Passive agent: when to pick によって over に
Use に for personal-experience and adversative passives, the "迷惑の受身" (nuisance passive) pattern: 先生に叱られた ("I was scolded by the teacher"), 雨に降られた ("I got rained on").14
Use によって for creation, discovery, decision, founding, election, and institution verbs, especially when the patient is a created work or an institutional act: この歌は秋元さんによって書かれた ("This song was written by Mr. Akimoto"); この建物は有名な建築家によって設計された ("This building was designed by a famous architect").1314
The に slot here would be misread as a beneficiary ("for") rather than an agent ("by"): この歌は秋元さんに書かれた means "this song was written for Mr. Akimoto," not "by him."13
この建物は有名な建築家によって設計された。14
"This building was designed by a famous architect."
The full に / によって split for the passive agent is a topic in its own right. The passive voice article treats the direct, indirect, and adversative passives together.
によって vs. によると
によって covers means, cause, agent, and variation. によると is restricted to the report frame, with a paired hearsay ending.97
A minimal pair on a weather example shows the split:
天気によって予定が変わります。7
"Plans change depending on the weather."
天気予報によると、明日は雨だそうです。9
"According to the forecast, it will rain tomorrow."
If you swap one for the other, the sentence breaks: 天気予報によって、明日は雨だそうです has a report-frame ending (そうです) with a non-report particle.
によって vs. にとって
にとって marks "for X, from X's point of view," the subjective evaluation reading. によって marks "by X, depending on X," the objective basis reading. The two particles share the same N + に___ surface frame, but they fill opposite logical roles.
The contrast lives in a minimal pair on the same predicate:
私にとって難しい問題。
"A problem that is hard for me."
私によって解かれた問題。
"A problem solved by me."
The dedicated にとって article owns the deeper sort.
によって vs. について / に関して / に対して
The speech-topic family (について, に関して) marks the topic of speech or writing. The directional-target compound に対して marks the target of action or feeling. The basis family (によって) marks means, cause, agent, or variation source.1 They look similar but never overlap.
If you substitute について for によって in a cause sentence, you produce a broken sentence: 事故について話した = "talked about the accident" (topic); 事故によって遅れた = "was late because of the accident" (cause).
For the topic-of-speech and directional-target compounds in detail, see the dedicated について, に関して, and に対して articles.
Good to know
Etymology: the verb under the particle is 因る
因る (yoru) is a godan intransitive verb meaning "to be due to, to be caused by, to depend on." Its て-form 因って became fixed as a compound particle in formal Japanese.2
The kanji 因 ("cause, factor") is a 5th-grade kyōiku kanji, with on'yomi イン and kun'yomi よ.る. It also lives in 原因 ("cause") and 因果 ("cause and effect").12
The variant spelling 依る attaches the same verb to a closely related sense ("to rely on"). Modern compound-particle usage almost always writes the form in kana.2
Marking a created work's agent with に instead of によって
A common error is to write 『源氏物語』は紫式部に書かれた, which reads as "Genji Monogatari was written for Murasaki Shikibu" rather than "by her." The に slot in a passive is reserved for personal-experience and adversative passives. For creation, discovery, invention, and institutional acts, mark the agent slot with によって:1314
『源氏物語』は紫式部によって書かれた。13
"Genji Monogatari was written by Murasaki Shikibu."
Treating によって and によると as interchangeable
If you pair a hearsay ending such as そうです with によって, you produce a broken sentence: 天気予報によって、明日は雨だそうです. The paired hearsay ending selects the report frame によると:9
天気予報によると、明日は雨だそうです。9
"According to the weather forecast, it will rain tomorrow."
Reading により aloud in casual speech
により is the written-formal twin of によって, comma-flagged in news, legal, and business prose. Reading it aloud in casual conversation makes the speaker sound like they are quoting a contract.34 If you hear により in a workplace or news context, parse it. If you are speaking casually, switch back to で or から.
English "by" splits five ways; によって inherits the load
In English, "by" carries the means ("by car"), the cause ("by accident"), the agent ("by Edison"), the basis ("by law"), and the depending-on / variation reading ("results vary by region"). によって covers the same five-way load in formal Japanese. That is why the four canonical N3 readings plus the によっては condition reading all sit under one form.56
A note on 法律により処罰される style headlines
Legal and news headlines sometimes drop the comma after により for compression: 法律により処罰される ("punished by law"), 台風により被害 ("damage due to a typhoon"). You should parse and recognise the pattern, but keep the comma in your own writing, since the comma is a register marker that signals the formal ladder.34
See also
- The にとって Compound Particle: For X / From X's Perspective
- Passive Voice (受身形): Direct and Indirect Passives
- The から Particle: From (Source and Reason)
- The より Particle: Than / From (Formal)
- ～そうだ (Hearsay): How to Say "I Heard That" in Japanese
- JLPT N3 Grammar Checklist: The Curated List