For authors getting a book ready to sell
Book Blurb and Amazon Description Generator
Paste your synopsis or drop your manuscript. Get back cover copy, an Amazon description ready for KDP, a one-line pitch and an ad hook.
Free to start. No card needed.
Copy sheet · a locked-island thriller
- Back coverThe ferry company's books balance. That's the problem. Forensic accountant Isla Moncrieff comes home to bury her father and finds twenty years of payments to a boat that sank the night her mother drowned.
- Amazon description · 640 of 4,000 charactersThen a storm shuts down the ferry. For a week, no one can leave the island, and the man who signed those payments is sitting in the only pub.
- One-line pitchTrapped on her home island by a storm, a forensic accountant must prove who sank the boat that killed her mother before the man who signed the payments silences her.
- Ad hookHer father's books balance perfectly. That's how she knows someone lied.72/150
What you'll get
Back cover copy, an Amazon description, a one-line pitch and an ad hook
- Back cover copy sized for a paperback
- An Amazon description ready for KDP, with its count
- A one-line pitch and a short ad hook
Examples
Book blurb examples
Three short blurbs in three genres, each built the way River builds yours: a hook, one person to root for, the trouble, and a stop before the ending.
| Genre | Example blurb | What it does |
|---|---|---|
| Romance | She came home to sell the bakery. He's the only one buying. Twelve years ago, Nora Quinn left Larkspur Bay with a packed car and a broken engagement. Now her grandmother's bakery is hers, and the only offer comes from Cal Bishop, the man who chose the family boatyard over her. Cal needs the building. Nora needs the money. One month side by side should be simple. | Both leads, the second-chance trope and what each one wants, then a closing line that promises the romance without spoiling it. |
| Cozy mystery | When the judge of the Halden Maple Festival is found face down in a sugaring vat, the village blames the newcomer. Retired school librarian Agnes Pike knows better. Armed with forty years of overdue-book detective work and the best gossip network in Vermont, she starts asking the questions the state police won't. But every family in Halden has a secret buried under the snow. | The crime, the sleuth and why she can solve it, in a light tone that tells cozy readers this book is for them. The culprit stays hidden. |
| Fantasy | In Carrow, every debt is paid in years of your life, and Tamsin Roe has been paying off her father's for a decade. She has nine years left when the Ledger House offers a deal: steal one contract from the Queen's archive, and the debt is cleared. No one has ever broken into the archive. The last thief who tried is still paying. | One rule of the world, tied straight to what the heroine could lose, plus a job and a reason it might be impossible. |
Written for this page to show the shape. The books and authors are invented.
Before and after
Your book in. Four jobs done.
It's a locked-island thriller. Isla Moncrieff is a forensic accountant who goes home to Ardsay for her father's funeral. She agrees to close out the books for his ferry company and finds payments to the boat that sank twenty years ago with her mother aboard. Then a storm shuts the ferry down for a week, nobody can leave, and the man who signed those payments is sitting in the island's only pub. Twist: her father wasn't the one who sank it.
Back cover The ferry company's books balance. That's the problem. Forensic accountant Isla Moncrieff comes home to Ardsay to bury her father and close his accounts. It should take a weekend. Instead she finds twenty years of payments to a boat that sank the night her mother drowned. Amazon description (640 of 4,000 characters, formatting included) ...Then a storm shuts down the ferry. For a week, no one can leave the island, and the man who signed those payments is sitting in the only pub. A tense locked-island thriller for readers who like their secrets buried deep. One-line pitch Trapped on her home island by a storm, a forensic accountant must prove who sank the boat that killed her mother before the man who signed the payments silences her. Ad hook Her father's books balance perfectly. That's how she knows someone lied about the night her mother drowned.
The twist stays out of all four pieces. That's what makes a reader open the book.
Why it works
What is a book blurb, and how long should it be?
A book blurb is the short sales copy on your back cover, and your Amazon description is the longer version on your book's page. River writes both from whatever you have: a few sentences, your synopsis or the whole manuscript. One doc holds four pieces: back cover copy, an Amazon description ready to paste into KDP, a one-line pitch for queries and bios, and a short ad hook. Each one introduces your main character and the trouble, then stops before the ending.
Blurbs go wrong in predictable ways. They summarize every subplot, name six characters, open with a vague question, or give away the twist that should make someone buy. River writes up to the moment the trouble peaks and stops on the question your reader needs answered. It uses your names and concrete details, keeps your tone, and never invents praise or awards. Romance gets both leads and the trope, a thriller gets the threat and the clock, and fantasy gets one world detail tied to the stakes.
Your back cover and your Amazon page do different jobs. The back cover shares space with your author bio, while KDP's description box allows up to 4,000 characters and follows its own rules, which River counts for you. For the bio beside your blurb, start with the author bio template. When the description is done, fill your KDP keywords, or build the whole listing with Publish a Book on Amazon. The one-line pitch also seeds the hook of a query letter.
What lands in your doc
What lands in your blurb doc
- Back cover copy of 100 to 170 words, with a hook line, rising stakes and no spoilers
- An Amazon description with its character count as KDP counts it, ready to paste
- A one-line pitch of 30 words or fewer for query letters, newsletters and social bios
- An ad hook short enough for ad text, written to avoid what Amazon's book ad guide flags
- Genre conventions handled for you: both leads for romance, the clock for thrillers
- Your real names and details in every piece, and never invented praise, awards or sales figures
How it works
From your book to four pieces
Paste what you have
Paste a description, your synopsis or chapter one, or drop in the whole manuscript file.
River finds the hook
It picks out your main character, the trouble, the stakes and the genre promise readers expect.
Get four pieces
Back cover copy, an Amazon description, a one-line pitch and an ad hook land in one doc.
Paste and use
Paste the description into KDP, send the back cover to your designer, or ask River to sharpen a line.
What KDP accepts in a book description
KDP's description box takes up to 4,000 characters, and every formatting mark counts toward that limit, so a bolded word costs seven extra characters, per its description help page. The editor supports paragraphs, line breaks, bold, italics, underline, small headings and lists. Pasting straight from Word or Google Docs can carry hidden characters, which is behind KDP's invisible characters error, as its troubleshooting page explains. Paste as plain text, then reapply bold and italics with the buttons above the box.
KDP's metadata guidelines rule out review quotes and testimonials, website links, emails and phone numbers, prices and time-sensitive offers, emojis, keyword lists and spoilers. Review quotes have their own home in the Editorial Reviews section of Author Central. KDP's own writing advice is short: aim for about a 150-word paragraph that is easy to scan, with a first sentence that draws readers in. Make the genre obvious, so the right readers stay and the wrong ones move on.
The ad hook is the shortest piece and the strictest. Amazon's book ad moderation guide says to avoid customer reviews, prices, unsupported claims, wrong capitalization or grammar, and provocative terms tied to specific sexual practices. All book ads must suit a general audience. River writes the hook to stay clear of those, in normal sentence case and short enough for ad text. The one-line pitch is your whole book in 30 words or fewer, so you can say it out loud when someone asks.
Questions authors ask
Common questions
What is a book blurb?
A book blurb is the short sales copy on your back cover that introduces the main character, the trouble and the stakes, then stops before the ending. In publishing, a blurb can also mean an endorsement from another author. This tool writes your own cover copy and description, and never invents praise, quotes or awards.
What's the difference between a blurb and an Amazon book description?
Both sell your book, but they live in different places. The blurb sits on your paperback's back cover, limited by the space there. The book description is the text on your Amazon page, where KDP allows up to 4,000 characters and rules out reviews, links and spoilers. River writes both from one core, sized for each place.
How long should a blurb and a description be?
There's no single rule for the back cover, but most blurbs run about 100 to 200 words so they fit beside a short bio; River writes 100 to 170. On Amazon, KDP's advice is about a 150-word paragraph with a strong first sentence, so River keeps fiction descriptions to 150 to 250 words.
What formatting does Amazon allow in a book description?
KDP's description box supports line breaks, paragraphs, bold, italics, underline, small headings and numbered or bulleted lists, and the larger heading sizes are not supported. River uses only the supported options. If KDP says your description has invisible characters, paste it as plain text and reapply bold and italics with the buttons above the box.
Can I put review quotes or my website in the description?
No. KDP's description rules exclude reviews, quotes and testimonials, plus website links, emails, phone numbers, prices and time-sensitive details. If you have strong review quotes, Amazon Author Central offers an Editorial Reviews section, which Amazon lists as a US-only feature. River leaves all of these out of your description.
Will the book blurb generator give away my ending?
No. Every piece builds to the point where things get worst and stops there, on the question a reader has to open the book to answer. Twists, reveals and the ending stay out. A romance can still promise its happily ever after, since readers of the genre expect that promise and it spoils nothing.
Can I use the ad hook in Amazon Ads?
You can try. Amazon checks every book ad against its moderation guide, which rules out customer reviews, prices, unsupported claims, wrong capitalization and provocative sexual terms. River writes the hook to stay clear of those. Amazon's moderators make the final call, so if a hook is sent back, ask River for a fresh one in the same doc.
Your next step
More for your book
Give your book the words that sell it
Paste your synopsis or drop in the manuscript, and get all four pieces in one doc you keep.