Book Pitch Generator: Seven Sizes of Pitch, One Book, and the Swap Test That Catches Generic Copy (2026)

An agent opens your email on a phone, on a train, between two other emails. One sentence gets read. Maybe two. By the end of the second, the agent has decided whether a third is worth the time.

That first sentence is your pitch, and you probably wrote it last, tired, after two years on the book itself. No wonder so many authors type "book pitch generator" into a search bar and hope a machine can do the part that feels like selling.

A machine can help. Most of the free ones won't, for a reason that is easy to see once you know where to look. This guide shows you what a pitch is made of, how to test one, and what a generator has to read before its output is worth sending.

---

First, a correction: you need more than one pitch

Writers talk about "the pitch" as if it were one paragraph. In practice a finished book needs a family of them, each a different length, each for a different reader. They nest inside each other like measuring cups.

Non-fiction adds an eighth: the book proposal, a document of overview, market analysis, comparable titles, chapter outline and author platform.

The useful thing about seeing pitches as a ladder is that every rung is built from the rung below it. If your logline is weak, your blurb will be padding around a weak logline, and your query letter will be a longer version of the same problem. Fix the small one first.

---

Why most pitch generators give you a pitch nobody can use

Here is the output a typical free generator returns when you give it "thriller, female detective, missing brother":

When a determined investigator uncovers a dark secret, she must race against time to save everything she loves before it's too late.

Read it again and count the words that belong to your book. There are none. "Determined", "dark secret", "race against time", "everything she loves" could sit on the back of four thousand novels, and agents have read all four thousand.

The generator isn't broken. It did what it could with what it was given, which was nine words. A pitch is a compression of a book, and you cannot compress something you never received. Any tool that asks for a genre and a sentence, and nothing more, can only hand you the average of every book in that genre.

The swap test

Here is a fast way to tell a real pitch from a filler one, whoever wrote it.

Take your pitch, and replace your book's title with the title of a different book in your genre. If the pitch still reads as accurate, it is not yet your pitch.

The example above passes for Gone Girl, The Silent Patient and most of the thriller shelf at an airport. A good pitch fails the swap test immediately, because it names something only your book contains: a specific person, a specific place, a specific impossible choice.

Run it on every rung of the ladder. Taglines fail it most often.

---

Four things every pitch is judged on

When an agent's assistant screens queries, the questions in their head are roughly the same each time. StoryWith AI's free query letter grader scores letters on exactly these four, from 1 to 10, and you can apply them by hand to a pitch of any length:

1. Hook. Does the opening make someone want the next sentence, and is it specific to this book?
2. Stakes. Is it clear what the protagonist wants, what stands in the way, and what they lose if they fail?
3. Voice. Does the pitch sound like the book? A comic novel pitched in a funeral tone is a mismatch an agent spots at once. Clichés and rhetorical questions ("What would you do if...?") cost points here.
4. Clarity. Can a stranger follow it? Two names, one conflict, no subplots, no backstory. Every extra character in a pitch is a speed bump.

A calibration note worth stealing from the grader's instructions: a 5 is a workable pitch with clear problems, a 7 is one an agent would read to the end, and a 9 or 10 is rare. If a tool tells you everything you wrote is a 9, it is flattering you, and flattery has never landed anyone an agent.

---

One invented book, pitched at every size

Theory is cheap. Here is a single (made-up) novel taken up the whole ladder, so you can see how each rung grows out of the one before.

The book: The Salt Ledger, a literary thriller of 92,000 words. Wren Abernathy, 34, investigates insurance claims in a fishing town on the north-east coast of Scotland. A trawler sinks with all hands. The crew list filed with the harbour master includes her brother Callum, who drowned eight years ago.

Tagline (under 12 words)

The trawler went down with six men. One died years ago.

Logline (one sentence)

When an insurance investigator finds her drowned brother's name on the crew list of a trawler that sank last week, she must choose between paying a claim that would save her dying hometown and exposing the fraud that may prove Callum never died at all.

Notice what the logline carries: a protagonist with a job, an inciting discovery nobody else could make, a goal, and a choice with a cost on both sides. Swap the title for any other thriller and it stops making sense. It passes.

Elevator pitch (about 30 seconds aloud)

It's a literary thriller set in a Scottish fishing town. Wren investigates insurance claims, and when a trawler sinks she finds her brother on the crew list, except he drowned eight years ago. The payout would keep the town's last boatyard open. Proving the claim is fraud would close it, and might mean Callum faked his own death and left her to grieve him. Think Ann Cleeves's Raven Black with the family weight of Jane Harper's The Dry.

Spoken pitches can be looser than written ones. The comps at the end do work that would take another paragraph: setting, tone, and the shelf it belongs on.

Catalog hook (about 50 words)

Six men went down with the Morven Lass. Wren Abernathy knows one of them was already dead. Her brother drowned eight years ago, and now his name is on a crew list, his signature on a claim. If she pays, the town survives. If she digs, she may find him.

Back-cover blurb (120–180 words)

The blurb opens up the middle of the story without giving away its turn. In The Salt Ledger it would introduce the town's reliance on the boatyard, the harbour master who signed the crew list and won't say why, and the moment Wren finds a recent photograph she cannot explain. It ends on a line the reader has to resolve by buying the book, which is the opposite of a synopsis. (For the full craft, see how to write a book blurb that sells.)

Query letter (250–350 words)

The query letter reuses the logline almost word for word as its opening, spends one or two paragraphs building to the choice, then gives title, genre, word count (rounded: "92,000 words", never "91,847") and two or three comps, then a short bio. Nothing invented: if Wren's author has no awards, the bio doesn't imply any.

Synopsis (1–2 pages)

The one rung where you spoil everything. The agent needs to see the ending works, so the synopsis tells them who signed the list, what happened to Callum, and what Wren chooses.

Look back up the ladder and you'll see it never introduces a new idea after the logline. Every longer pitch is the logline with more room. That is why the logline is where your effort, and any generator's effort, belongs.

---

What a generator has to read to do this for your book

Everything that made the Salt Ledger pitches work came from inside the book: the trawler's name, the harbour master, the boatyard, the photograph. None of it could come from a genre dropdown.

So the honest test of any book pitch generator is one question: what does it read before it writes?

The last row is the one that matters once the book exists. You have already written the specific details. A generator that reads them doesn't need you to remember them at midnight.

---

Why authors use StoryWith AI to build their pitch

We make StoryWith AI, so weigh this section knowing that. Everything above works without it.

StoryWith AI is a writing studio where your manuscript, story bible and revision notes live together. Its Pitch Kit sits at the end of that process, and that position is the whole point: by the time you open it, the tool has already read your book.

It writes from your chapters, not from a prompt. When you generate the blurb and query kit, StoryWith AI assembles a synopsis from your own chapter and scene summaries, along with your title, genre, tone and premise, and drafts from that. Characters, places and turns in the pitch are ones that exist in your manuscript.

It refuses to pitch a book that isn't there yet. If your draft is under 5,000 words, the Pitch Kit won't generate. That sounds like a limitation, and it is a deliberate one: a pitch written from a thin draft invents a book you haven't written, complete with comps for a story that doesn't exist yet.

One click fills most of the ladder. A single generation returns:

• a one-sentence logline (the "hook")
• 3 alternative taglines
• 4 alternative titles, which you can adopt with "Use this"
• 3–5 comp titles, shaped by the comparable authors you chose when you set up the book
• a 120–180 word back-cover blurb that ends on a hook line
• a short third-person author bio
• a 250–350 word query letter, signed with your name

No "[Author Name]" placeholders. The kit asks for your author name before it spends a credit, and is told never to write bracketed template tokens or invent contact details. You get a letter you can actually send, not a form to fill in.

Non-fiction gets a real proposal. For non-fiction books the Pitch Kit builds the standard submission package instead: a 200–300 word overview, a market analysis, comp titles with year and publisher, a chapter-by-chapter outline from your own chapters, suggested sample chapters, and an author platform section.

It tells you what's missing before you send. Next to the generated copy is a pre-publish validation (premise written, protagonist defined, at least three chapters, no empty chapters or scenes, word count over 10,000) and a 10-item submission checklist: logline locked, synopsis written, blurb finalised, comps chosen, two bio versions, query drafted, beta feedback collected, an edit pass done, metadata selected.

The cover and title live in the same place. Cover art (painterly, minimal or photographic) and title alternatives sit in the same kit, so the tagline, title and cover are designed to agree with each other instead of being made in three different tools.

It can be checked against real readers first. Before you pitch, StoryWith AI's reader personas and feedback sessions show where readers lose interest. A pitch that promises a fast thriller is a problem if real readers stall in chapter nine, and you'd rather find that out before an agent does.

No book in StoryWith yet? Two free tools, no account

• Query letter generator: answer six questions (genre, word count, protagonist, goal, stakes, plus optional title, comps and bio) and get a letter in the standard agent format, with notes on what to personalise. It won't invent awards or credentials, and it won't add comps you didn't give it.
• Query letter grader: paste a letter you've written and get the four 1–10 ratings above, an overall score, a two-sentence verdict on whether an agent would request pages, and up to five line-level edits quoting your own wording.

---

When not to use a pitch generator at all

Generators are bad at a few things, and it's better to know which:

• Before the book has an ending. If you don't know what your protagonist chooses, no tool can pitch the choice. Write the draft.
• When you can't say the logline yourself. Use the generator's version as a sparring partner, then rewrite it until you could say it aloud to a stranger without reading it. Agents can tell when an author doesn't sound like their own query.
• For comps you haven't read. Treat generated comp titles as a shortlist to check. Read, or at least research, every book you name, confirm it was published in the last five years or so, and drop any that are bestsellers so huge they make you sound unrealistic.
• As the last pass. Every generated pitch needs a human final read for voice. The machine gets you from blank page to strong draft. The last 10% is yours.

---

Questions authors ask about pitch generators

Is it acceptable to send an agent a pitch an AI helped write? Agents judge the letter and the pages. What matters is that every claim in it is true, the voice matches your book, and you can talk about it on a call. Use the draft as a draft.

What's the difference between a logline and a tagline? A logline explains the story (who, what they want, what's in the way). A tagline sells a feeling and usually leaves the explanation out. Agents ask for loglines; covers and ads use taglines.

How long should a book pitch be? It depends which rung you mean: under 12 words for a tagline, one sentence for a logline, 250–350 words for a query letter. See the table at the top.

Can a pitch generator pick my comp titles? It can suggest them. You must verify them. StoryWith AI's suggestions start from the comparable authors you named when you set up the book, which keeps them closer to the shelf you're actually aiming at.

Does StoryWith AI write my book for me? No. You write the book. The analysis tools read and diagnose your manuscript without rewriting it, and the Pitch Kit drafts marketing copy about your book. Any writing help in the editor is something you choose to call up, line by line.

I'm writing non-fiction. Do I need a query letter or a proposal? Usually a proposal, often with a short query on top. StoryWith AI's non-fiction Pitch Kit builds the proposal sections from your chapters.

---

Where to go next

Start small. Write the logline, run the swap test, score it on hook, stakes, voice and clarity, and only then climb the ladder.

If your manuscript is already in StoryWith AI, open the Pitch Kit from the Publish page and generate the full set in one go. If it isn't, start with the free query letter generator and see what your book looks like at 300 words.

And if you're unsure the book itself is ready to pitch, read Is My Book Ready to Query? first. The best pitch in the world can't fix pages that aren't ready, but it can stop good pages from being skipped.