How many review readers do you need to get 20 reviews in launch week?

To put 20 reviews on your Amazon page in launch week you need somewhere between 50 and 180 people to say yes to a review copy, depending on where those people come from. Readers from a vetted service who have asked for your book review at a much higher rate than people you recruited with a free download link. The working below runs backwards from 20, with every assumption written down so you can swap in your own numbers after your first launch.

The funnel

A review copy goes through four stages before it becomes a review you can count.

1. Sign-ups are the people who asked for the copy or accepted your invitation.
2. Downloads are the people who opened the link and took the file, because some never do.
3. Reviews posted are from the people who finished the book and wrote something, anywhere.
4. Reviews on Amazon in the week are the ones on the right page, in time to count.

Each stage loses people, and the losses multiply. The question is how much each stage loses, and that is where the published figures come in.

What the services publish

We checked the four services authors most often name, on 1 November 2026. Two publish a rate and two do not.

• BookSirens says on its pricing page and in its support articles that it maintains a site-wide review rate of 75%, meaning three downloads in four end in a review on average. Its support page adds that some books have 90% review rates and others have less than 50%, and that the book's quality is the main determinant. It also says readers you invite from your own team will behave differently from BookSirens' own readers, so the 75% is about their community.
• NetGalley's 2026 community update reports a 38% average monthly feedback rate for digital review copies and 57% for audiobooks. That is feedback per approved reader, across a membership of over 700,000 readers, librarians, booksellers and press, most of whom are reviewing traditionally published books.
• StoryOrigin publishes no average. It shows you each reviewer's completion rate from previous review copies before you approve them, and copies start counting towards a reader's stats after two weeks.
• BookFunnel publishes no average either. Its Certified Mail feature sends watermarked copies to a team you supply and reports who downloaded, which is useful for your own numbers but tells you nothing about other authors' readers.

We found no published rate from any service for reviews posted within a fixed week of release. All of the figures above are reviews posted eventually.

Two assumptions of our own

The published rates measure reviews per download or per approval. The funnel needs two more numbers, and these are our assumptions, not anybody's statistics.

• Downloads per sign-up: 70%. Some people sign up and never open the email. Your delivery tool will show you the real figure after one campaign.
• Reviews on Amazon within launch week, as a share of reviews posted: 80%. Some reviewers only post on Goodreads, some post in week two, and Amazon's Community team can take a few days to approve a review after it is submitted, according to KDP Help.

With that second assumption, 20 Amazon reviews in the week means 25 reviews posted.

The arithmetic

The downloads column is 25 divided by the rate, rounded up. The sign-ups column is that number divided by 0.7, rounded up. For NetGalley the rate is per approval rather than per download, so the sign-ups column for that row is a stand-in rather than a like-for-like figure.

A worked example

Suppose you are launching your second novel with a reader list of 600 and no service. You email the list offering review copies and 150 people request one. At 70%, 105 download. If a quarter of them review, you get 26 reviews posted, and at 80% on Amazon in the week, 21 Amazon reviews. You have hit the target with one to spare.

Now suppose the same book is your debut and you have 90 sign-ups from a Facebook group. At 70%, 63 download. At 20%, 13 review, and 10 land on Amazon in the week. You are half way. The fix is either more sign-ups, which means starting earlier, or a vetted service alongside your own team. At BookSirens' published rate, 34 extra downloads would add about 25 reviews, and BookSirens charges $10 to list a book plus $2 per reader who downloads on its pay-as-you-go plan, or $100 a year flat, according to its pricing page.

What moves the numbers

Three things change the rate. Time: an 80,000-word novel is over five hours of reading at 250 words a minute, so send copies at least three weeks out. Reminders: StoryOrigin sends them automatically, BookFunnel lets you schedule them, and a plain email from you on release day with the Amazon link does the same job. Selection: a reader who asked for your book and has reviewed before is worth several who clicked a free link, which is why services that show completion rates exist.

Give readers a copy they can only get by asking. The Indie Author Toolchest does this with a request link on your author page: you approve each request, the reader gets a watermarked copy on a link that expires after 14 days, and you can see who downloaded. Then write your own numbers down after the launch. Once you know your readers download at 60% and review at 35%, the table above becomes yours, and the next launch needs no guessing.

For the rules on what you can and cannot ask reviewers to do, and the emails to send them, see running a review team without leaks or lost reviews. If you are deciding whether to run a preorder alongside the review copies, KDP preorder or straight to release works through that. To grow the list the sign-ups come from, start with newsletter swaps and group promos.

Sources: BookSirens pricing and its support article What is the expected review rate; NetGalley's 2026 community update; StoryOrigin on review copies; BookFunnel Certified Mail; KDP Help on customer reviews. All read on 1 November 2026.