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Sentence Diagram Generator
Type one English sentence. Get a labelled diagram of how it is built — clause by clause, component by component, with the original sentence coloured to match.
Try one of these
How the sentence diagram generator works
Three steps, about two seconds — the same analysis engine the Split Sentence browser extension runs in your browser.
- 1 Paste or type one English sentence, up to 300 characters.
- 2 The analyzer finds the clauses first, then splits each clause into grammatical components and gives every component a role.
- 3 Read the diagram: the sentence is coloured by role, and below it each component sits on one baseline in reading order.
Example diagrams
Three sentences that cover most of what a learner needs to see: a plain core, a relative clause in the middle, and a two-clause sentence.
Subject + predicate + adverbial — the core every diagram starts from.
The cat sat on the mat.
- The cat — who does the action
- sat — the finite verb
- on the mat. — a prepositional phrase saying where
Subject + intransitive verb + adverbial.
A relative clause splitting the subject from its verb.
My sister, who lives in Berlin, teaches English.
- My sister, — the head noun
- who lives in Berlin, — modifies "my sister"
- teaches — the main verb
- English. — what is taught
Subject + relative clause + verb + object.
Two clauses: a condition up front, the main clause after the comma.
If it rains tomorrow, we will stay home.
- If it rains tomorrow, — the condition
- we — of the main clause
- will stay — modal + verb
- home. — where we stay
Adverbial clause + subject + verb + adverbial.
What the diagram labels mean
The tool uses the same eight role names as the extension, so a diagram you see here matches the one you see on a web page later.
- SUBJECT
- Who or what the clause is about: the noun phrase the verb agrees with.
- PREDICATE
- The finite verb (plus auxiliaries and modals) that makes the clause a clause.
- OBJECT
- What the verb acts on — direct or indirect object.
- PREDICATIVE
- What the subject becomes or is, after linking verbs such as be, seem, become.
- ATTRIBUTE
- A modifier that sits inside a noun phrase: articles, adjectives, possessives.
- ADVERBIAL
- Where, when, how or why: adverbs and prepositional phrases that modify the whole clause.
- ATTRIBUTIVE_CLAUSE
- A relative clause (who / which / that) that modifies a noun.
- ADVERBIAL_CLAUSE
- A dependent clause acting as an adverbial: condition, time, reason, concession.
Using it as a sentence structure analyzer
A grammar checker tells you that something is wrong. A sentence structure analyzer shows you how the sentence is put together, which is the part that transfers to the next sentence you write.
That is also what a sentence structure analyzer does, step for step: parse the sentence, decide how many clauses it has, name the type of each clause, then say which role every phrase plays inside it. Only the output differs — a diagram you can read at a glance instead of a paragraph of prose.
Start with the core. Every clause has a predicate — the finite verb, with its auxiliaries and modals. Unless the clause is imperative, it also has a subject. Objects, predicatives, attributes and adverbials hang off that core.
Then look at the edges. Relative clauses and adverbial clauses are where long sentences get hard: the diagram shows exactly which noun a relative clause attaches to, and which clause an adverbial clause modifies.
Read the diagram top to bottom, left to right, and say the roles out loud. That sentence — "subject, verb, object, adverbial" — is the pattern you will recognise next time.
Frequently asked questions
Is the sentence diagram generator free?
Yes. You get 20 free diagrams without an account — the same trial the Split Sentence extension uses. No card and no sign-up; the counter is shown after each diagram.
What kind of diagram does it draw?
A component diagram: the sentence is split into clauses, then into subject, predicate, object, predicative, attributes, adverbials and dependent clauses, each labelled with its role and colour-matched to the original text. It is deliberately not a hand-drawn Reed-Kellogg fork — a fork the analyser is not sure about teaches the wrong structure.
Is this the same as a sentence structure analyzer?
Functionally yes. It parses the sentence into clauses and labels every component — subject, predicate, object, predicative, attribute, adverbial, dependent clause — which is what a sentence structure analyzer reports, except the output is a diagram instead of prose. What it does not do is grade grammar or rewrite the sentence.
How long can the sentence be?
Up to 300 characters, one sentence at a time. Multi-clause sentences are split into up to four clauses, so conditionals and relative clauses are fine. A whole paragraph is not.
Does it work for English learners?
That is what it is for. Role names are translated when the interface language is Chinese, and every component can carry a short note explaining what it does — the same notes the extension shows on hover.
Do I need to install anything?
No. The tool runs in the browser, on desktop and mobile. If you want the same diagram while reading other websites, there is a Chrome and Edge extension — its interface is currently Chinese only.
Is my sentence stored?
The sentence is sent to the analysis service to be diagrammed and is not saved with your account — there is no account. Only usage counters are kept, so the free trial can be enforced.
Diagram any sentence you read
The Split Sentence extension draws the same diagram inline on any web page, keeps the sentences you save in a practice book, and runs the fully local translation model when you want a paraphrase instead.
Pricing, offline package and FAQ →One thing to know first: the extension interface is currently Chinese only. The diagrams and grammar labels match this page, but its buttons and settings are in Chinese.
Desktop only: the extension installs in Chrome or Edge on a computer — not on phones or tablets.
Also available on Chrome Web Store Edge Add-ons