Sentence Structure Analyzer – Free Sentence Checker
Paste any sentence and get an instant breakdown: its type, word count, average word length, a subject and verb guess, and a clause estimate. Handy for homework, editing, and learning how sentences work. Free, no sign-up.
Basic analysis — this tool uses simple word-position rules, not a full parser, so complex sentences may be parsed imperfectly. Everything runs in your browser; your text never leaves your device.
What Is Sentence Analysis?
Sentence analysis means breaking a sentence into its parts: what type it is, how many words it has, and which words do the jobs of subject and verb. There are four sentence types in English. A declarative sentence states something (“The cat sleeps.”). An interrogative sentence asks a question (“What time is it?”). An imperative sentence gives a command (“Close the door.”). An exclamatory sentence shows strong feeling (“Wow, that is amazing!”). The subject is who or what the sentence is about; the verb is what the subject does or is. In “The cat sleeps”, the subject is “cat” and the verb is “sleeps”. Finding those two words is the first step to understanding — and fixing — any sentence. Basic analysis — this tool uses simple word-position rules, not a full parser, so complex sentences may be parsed imperfectly. It is a learning aid and a quick checker, not a grammar engine: passives, relative clauses, and compound subjects can fool its guesses.
How to Use This Sentence Structure Analyzer
- Type or paste a sentence into the box — one sentence at a time works best.
- Click Analyze sentence.
- Read the breakdown: sentence type, word count, average word length, clause estimate, and the subject and verb guesses.
- Use Copy result to paste the breakdown into your notes or homework.
Sentence Analysis Examples
| Sentence | Type | Words | Avg. word length | Subject | Verb | Clauses |
|---|---|---|---|---|---|---|
| The cat sleeps. | declarative | 3 | 4 | cat | sleeps | 1 |
| What time is it? | interrogative | 4 | 3 | it | is | 1 |
| Close the door. | imperative | 3 | 4 | you (implied) | Close | 1 |
| Wow, that is amazing! | exclamatory | 4 | 4 | that | is | 1 |
| She runs every morning. | declarative | 4 | 4.75 | She | runs | 1 |
| The quick brown fox jumps over the lazy dog. | declarative | 9 | 3.89 | quick | brown | 1 |
| The cat sleeps and the dog barks. | declarative | 7 | 3.71 | cat | sleeps | 2 |
| I stayed home because it rained. | declarative | 6 | 4.33 | I | stayed | 2 |
Notes on the guesses: commands have an implied subject (“you”), questions report the auxiliary verb (“is”), and the subject guess for “The quick brown fox…” is “quick” — the word after “The” — because the tool’s simple rule takes the first content word after an article. That is the documented heuristic limit: real grammar would say the subject is “fox”. Average word length counts letters only (35 letters ÷ 9 words = 3.89 for the fox sentence).
Where to Use Sentence Analysis
- English homework — check the type, subject, and verb of a sentence before handing it in.
- Learning English — see how declarative, interrogative, imperative, and exclamatory sentences differ.
- Editing your writing — spot long, clause-heavy sentences that are hard to read.
- Teaching grammar — a quick, visible breakdown for classroom examples.
- Test preparation — practise identifying sentence types and parts of speech.
- Writing variety — if every sentence you write is declarative, mix in a question or a command.