When I launched Honest Fibs the other day, I was pleasantly surprised to find out that with just a couple of dozen sales in a few days, it had reached the phenomenal sales rank of some #40,000.
This got me thinking: how is that even possible? I don’t think any of my older works have performed so well, even when they sell bigger numbers – say during a promo.
Then I came across a great resource, courtesy of The Passive Guy: an educated guess as to how Amazon’s ranking algorithm works, by John Doppler of Self-Publishing Advice. I examine his points here and look at how you can use them to increase your own sales.
Amazon’s Sales Rank
As a closely guarded secret, Amazon’s sales rank remains a perpetual source of confusion and myth. Authors find themselves asking questions like this all the time:
- “Why did my sales rank go down when I sold more books this week?”
- “Why did my sales rank go up when I didn’t sell anything?!”
- “How did the sales rank of this book leapfrog over mine when I’ve sold ten times as many books?”
For example, why did Honest Fibs hit #40,215 in its first week of launch, after only a couple of dozen sales?
Amazon won’t disclose their proprietary algorithms, but thanks to some clever analysis by indie authors, that formula has been reverse engineered. And once you understand that formula, the quirks of sales rank make much more sense, and you can use them to your advantage.
The basics of Amazon’s sales rank algorithm are surprisingly simple:
- Each sale or download of a product counts as one point toward a hypothetical “rank score”.
- Depending on the day, the preceding day’s score decreases by half, and is added to today’s points.
- For each category on Amazon, books are ranked based on their current scores.
There are some caveats, though. For example, as author Carolyn McCray points out, #2 would have you think that a book selling copies worth 128 “points” on Day-1, then never sells another copy, would see the following ranking:
- Day-1 128 points
- Day-2 64 points
- Day-3 32 points
- Day-4 16 points
- Day-5 8 points
- Day-6 4 points
- Day-7 2 points
- Day-8 1 point
In fact, there are multiple drop-off points, the first being the 24-hour window. After 24 hours your sales numbers are cut in half, but this does not happen daily. As a matter of fact, you are stable for several key periods: a week, a month, 3 months, 6 months, 12 month and 18-months.
That is why most people price too high for too long after a promotion and then suddenly, after a month of steady sales, fall from the sky in flames.
The most severe of these drops is the 30 day one. If you don’t bolster sales and convince the algorithm that you can still sell, you will fall off a rankings and sales cliff after a month.
Other factors include the following:
Sales rank is relative to other books
A book does not exist in a vacuum. As your book rises in sales rank, it will displace other books. As other books rise through the ranks, your book may be pushed downwards.
This counterintuitive feature of the algorithm is responsible for more confusion than any other.
The more recent the sale, the more weight it has
Because the formula weights sales by recency, the effect of a sales spike quickly fades. The algorithm favors steady sales over a dramatic surge.
Consider the two books below (Figure 1). Book A experiences slow, constant growth for the first two weeks. Book B offers a promotion which results in an explosion of sales, but those sales quickly settle back to normal levels once the promotion ends.
At the end of the second week, Book A holds a higher sales rank — and has better visibility — even though Book B sold over three times as many copies.
In the long run, steady, organic growth outperforms sudden bursts of activity.
That is why publishing success is a marathon, not a sprint, so authors should be focused on long-term success.
Enrollment in KDP Select/Kindle Unlimited does not confer any direct advantage to sales rank
Titles in KDP Select do not receive higher placement just for enrolling in the program. However, downloads of books through Kindle Unlimited and Kindle Online Lending Library are treated as sales, and they are credited immediately.
A download is immediately recorded as a sale in the sales rank algorithm, regardless of what percentage of the book is read.
High sales rank does not guarantee high placement in search results
Sales rank plays but a minor role in determining the order of Amazon search results. Other factors such as relevance, keywords, sales history, product listing quality, and available inventory may influence Amazon’s algorithms. Therefore, a book with high sales rank may appear later in search results than lower-ranked books.
It takes twice as many sales to hit a rank than it does to maintain it
Because each day’s sales rank builds on previous sales, twice as many sales are needed to initially achieve a rank as compared to maintaining that rank. In other words, an author may need 40 sales to initially hit a given rank, but once that momentum is established, they will only need 20 sales per day to maintain that score (sales rank may still fluctuate due to the performance of other titles around it.)
Similarly, if no sales are made, the book’s score is cut in half on the following day.
Twice as many sales are needed to hit a rank initially; each day without sales halves a book’s score.
Pre-orders are counted immediately
Pre-orders are counted on the day the book is ordered, rather than on the date of the book’s release. This explains how books that have not yet been released may have a high sales rank, a common source of confusion.
Sales momentum is a key factor in the algorithm. The early boost from pre-orders have the potential to propel a title onto the Amazon charts faster and for a longer period of time than a launch day blitz alone would.
Let me repeat the algorithm’s key points:
- Sales rank is relative, and changes in rank may be due to the performance of other books
- Higher sales rank does not mean higher overalls sales
- It takes half as many sales to sustain a rank as it does to initially hit it
- A launch day blitz may briefly attain a high sales rank, but steady, organic growth will sustain it
- Pre-orders increase visibility and jump-start your book’s sales rank
- Kindle Unlimited downloads immediately affect your sales rank, regardless of whether they are read
Taming the Algorithm
What does all this mean for your marketing?
You need to be running some form of significant promotion monthly and rotate that around your library. Have each of your books on sale, countdown deal or giveaway each month. Advertise the promotion, to make the most of it. And be sure to have a big push for your “Flagship” titles once every six months, or they could die away.
Amazon ads, Google Adwords, and FB ads can also help keep a steady stream of sales to help build “traction” inside the algorithm.
Why is this important? Because the more “banked” sales you have, the more responsive your title is to a sales push. As author Carolyn McCray explains, flagship title will rise much more quickly through the rankings under the exact same sales push than a younger title with less historical sales to its credit. And the difference can be huge. McCray mentions that her better-selling titles can rise as much as quadruple the rankings than a less selling one – with the same amount of units sold. The key factor is long-term sales and this “traction” you have inside the algorithm.
You can think of Amazon’s algorithm as an equation that is constantly downgrading your chances at getting into the alsobot queue – that list of books under each title page that reads, “Customers who bought this also bought…” This is the single largest sales source on Amazon, and you need to keep reminding the algorithm that you can sell enough books to keep those alsobot slots alive. So, run strategic promotions to both maximize your ROI and keep the algorithm happy.
But this also means that you need to write a lot. You need at minimum 12 books/collections out to really make a go of this, and even more is better so that you can constantly have marketing promotions in the mix.
Still, volume alone does not sell books. No one will talk about your book if they can’t find it. The vast majority of people on Amazon find their books through the alsobot and the bestselling lists. Both of which are predicated on you selling enough books to keep your name out there.
This doesn’t happen by magic. It happens by promotion. And promotion is only successful if you understand how the algorithm works!
You can check out some great comments on The Passive Guy and on Self-Publishing Advice.
I think, very high thought writing
Very helpful tutorial on sales rank. However, I’ve noticed that sales rank does not correlate well to the coveted alsobot link. My book has an alsobot link to books often with lower (i.e. higher number) rank, yet the lower rank books do not link back to me. What other factors are at play here? Thanks!
That’s a good question. I’ll share if I find out something 🙂
Thanks for the valuable information! On to the next promotion.
A pleasure! I’m glad you found it useful 🙂
Wow that is so complicated. No wonder I’m floundering on Amazon! And it will take forever till I can produce 12 books… I’m not a churn em out every month kind of writer! So I guess what I’m saying is I have no chance. Back to the drawing board… sigh! ?
Lol – I know the feeling, and I’m almost at the 12 books point 😀
Wow that’s good going, well done Nick!
Thanks! It’s a good thing I’ve got you lovely guys to spur me on 🙂
Thank you for sharing this, Nicholas, and it’s always intriguing to gain information on Amazon’s obscure algorithms but, to tell you the truth, I’ve long stopped fussing or monitoring my books’ rankings, deciding it’s futile to try to understand them. I just do my posting, my occasional free/kcd promos, and accept luck also comes into the equation. Selling books is like selling music records or movies. It’s all about timing. How do you control that? As you said, a book does not exist in a vacuum. You never know what the competition will be when you make your efforts. Besides, I presume Amazon keeps tweaking the algorithms anyway, always one step ahead of us sniffing around, LOL
Lol – I hear you 😀
This is a bloody brilliant post, Nick, but it also made my head hurt. I don’t think there’s an algorithm for that.
Sure there is:
1. Walk to pharmacist.
2. Buy aspirins.
3. Pop lid.
4. Insert aspirin into mouth.
5. Add water.
Thanks Nick. I appreciate the work you put in to this, but I thought it more expedient to get my manservant to do it instead.
Why – did he, too, have a headache?
Yes, but for entirely different reasons.
going to come back to read this in more detail, I now have a book marketing folder which is getting a lot of your posts added to it!
Aw, that’s sweet! Thanks 🙂
Another fabulous post, Nicholas. This will help with my launch on the 31st of May…I hope. 🙂
I sure do hope so – and thanks 🙂
Thanks as always for sharing this very interesting info, and reminding me that I’m quite overdue to run a promo! 🙂
I should schedule one myself 😀
Thanks for sharing this information, Nicholas. 🙂 — Suzanne
A pleasure! Hope you find it useful 🙂
I think that signpost is missing a direction. One sign should point straight down and say Brain Meltdown.
Hats off to anyone who can wade through self-publishing data that changes every week. Personally, I have to wear a hat to keep my head from exploding.
I appreciate the work that goes into analyzing the Amazon mindset. But if I have to apply such marketing algorithms after writing nine books I’ll have to trade in my sunhat for a crash helmet.
It’s not scientific, but I’d rather believe in serendipity than navigating the swampland of Amazon. Whatever lurks in there can’t be healthy for a writer’s sanity. I see the signpost for that points up.
Lol – true enough. Not to mention that, the moment you manage to master all that, Amazon/Facebook/Google change everything and it’s back to square one…
Well, I can’t say I’m thoroughly enlightened. I never was good with math :-). I really need to put together a promotions calendar as I get so swamped, I let that slide. Good reminder, Nicholas!
Same here! So much to do, not enough hours in a day…
Here’s an extremely informative article that may change your thinking a bit. “Amazon’s algorithm isn’t a secret, it’s a standard A9 algorithm.” Like you, I’ve read numerous articles about AZ algorithm, and they all basically say the same thing, as you’ve so eloquently explained in this post. But now, I’m not sure what to believe. This article shocked me, but the author is very convincing. Check it out. I’d love to hear your thoughts.
That’s interesting, Sue. Methinks it’s time to change my keywords to ones that take into account sub-genre, mood, and location. It seem I’ve been barking up the wrong tree, totally D:
I found it interesting, too, Sarah. Good luck with your keywords!
That’s a great resource, thanks for sharing. She gives me the impression of overblowing the “myth-busting” aspect of the post (for example when she mentions that the algorithm is not a secret but a standard A9 one, not a secret one, then she admits that A9 won’t be interviewed because of confidentiality clauses), but it’s otherwise very interesting. Most of what she says doesn’t really contradict the info here.
I thought you’d like this one, Nicholas. Yeah, I noticed that wording also. Maybe by combining the two articles we’ll cover all basis. Wishing Electra a Happy Mother’s Day!
You read my mind!
Thank you! 🙂
Good information – e were just discussing this in my critique group.
That’s great! Send them this way 😉
I’ve had run-ins with algorithm’s before, and it wasn’t pretty. That kind of math has no meaningful use on an individual scale. It explains a lot about the weird rankings.
Thanks! It does explain some of the stranger hiccups my ranks go through periodically 🙂
A lot to process,but interesting. Thanks for sharing, Nicholas. 🙂
A pleasure! Hope you find it useful 🙂
Me too. I’m in information overload.
Sigh… Tell me about it 🙂
Interesting. Though, what about reviews? I remember reading that they have an impact on ranking as well. The newer the review, the more influence it has over the numbers. Is that still part of the algorithm?
I agree, and have noticed that. The author claims otherwise, but in my experience they do play a part.
Honestly, I’ve seen so many ‘I broke the algorithm!’ posts over the years that I don’t think we’ll ever get a true answer. That and Amazon could be changing it every few months.
That last bit is a constant source of frustration 🙂
I’ve seen so many authors spend more time on the algorithms than writing new stuff. Nearly went down that path when I remembered I’m not a numbers person and was starting to no longer have fun. I’m a simple man. 😛
With simple pleasures. Like telling the story of a jeep. And a homicidal maniac.
It’s funny how Cassidy gets overlooked at times. I really hope I can boost her exposure and fandom in the sequel.
All good comes to her that waits.
Or takes what she wants by the horns. 🙂
Yep. That’s our girl.
Whew, that’s a lot of information! And it drives home how terrible I am at marketing, lol. I think what I’ll take away from this is A) do pre-ordering! and B) do constant promotions across your various titles. Also C) write more books. Which I’m off to do now!
Lol – I think you’re great at marketing, as you have a lovely personality that shines through every word you write. As for (a), in fact there’re enough who claim that pre-orders actually do little for a book. Hmm…
I enjoyed and appreciated reading this, Nicholas. It gave me many points to ponder…thank you so much for the information. 🙂 (And happy Saturday!)
A pleasure! Hope you find it useful 🙂
I certainly did! 😀
I wanted to see if I could come up with something to add to the discussion, which is the only reason why I didn’t reblog your insightful post. I am still struggling with that, so I might just reblog it anyway. 😉 (We’ll see!)
I also was finishing up another edit for a client, which is one reason blogging on my end has been a bit scarce. 😉
Well, reagrdless of whether you reblog or not, thanks for the thought 😀
You’re most welcome. (And I did reblog from your WP site, just now.) I told people to read your blog regularly; they are missing out big-time if they don’t. 😉
Mwahahaaaargh! Only another 10 years and I’ll have written enough books to make a go of this! Very interesting article though. I never look at the sales rank of my books. That way lies despair for me as I have too many calls on my time to write more than three to five hours a week so my production rate is somewhat slow. It is very useful knowledge though and answers a number of questions as to why the rankings on some of my books are bizarrely high compared to others. Food for thought, too.
Meh, sales ranks. Who needs ’em.