How are Amazon / b&N sales ranks calculated?

You may find a thread or two if you do a search. I know it's been chatted up here within the past few months.

Amazon adjusts it sales ranking in real time. It is a complex system ,and amazon make adjustments, But it is roughly this

Rank Copies sold/per day

1............ 3000
10........... 650
100..........100
1000.........13
10,000...... 2,2(11 copies every 5 days)
1,000,000.. 0,0006(3 copies every 500 day)

Obviously ,there are ranking numbers in between and I have seen books ranked over 4,000,000,which probably means, never been sold on Amazon.

stephenf said:

Amazon adjusts it sales ranking in real time. It is a complex system ,and amazon make adjustments, But it is roughly this

Rank Copies sold/per day

1............ 3000
10........... 650
100..........100
1000.........13
10,000...... 2,2(11 copies every 5 days)
1,000,000.. 0,0006(3 copies every 500 day)

Obviously ,there are ranking numbers in between and I have seen books ranked over 4,000,000,which probably means, never been sold on Amazon.

Click to expand...

I think that's a little off. If you sell one copy in about three weeks, the rankings will be over the million mark already. It jumps very quickly and slows down the longer there are no sales.

Also, it's not real time. It's updated about once an hour and BN updates once a day but their rankings are calculated differently.

Last of all, if there is a ranking on either site, there has been at least one sale. They won't list a ranking until a copy has sold.

HTH clear up some confusion!

wilhem spihntingle said:

Thank's everyone. Very helpful. Also on Amazon, I see there is a genre ranking under the sales ranking. It doesn't show up for all novels though, anyone know why that is?

Click to expand...

I'm pretty sure the genre rankings only show up if the book is in the top 100 for that genre.

Kate_Sherwood said:

I'm pretty sure the genre rankings only show up if the book is in the top 100 for that genre.

Click to expand...

I believe this is true. In addition, the book has to have been added to the genre categories. Some of my epublishers do this, some don't.

Melanie Nilles said:

I think that's a little off. If you sell one copy in about three weeks, the rankings will be over the million mark already. It jumps very quickly and slows down the longer there are no sales.

Also, it's not real time. It's updated about once an hour and BN updates once a day but their rankings are calculated differently.

Last of all, if there is a ranking on either site, there has been at least one sale. They won't list a ranking until a copy has sold.

HTH clear up some confusion!

Click to expand...

The figures shown are Amazon's ,not made up by me.It is out-of-date but the principle remains true. If you have some statistics that prove the graft to be wrong, pleas post them,or are you just expressing a personal opinion?

Amazon operate in real time.If a book seller adds books to Amazon stock
of books, Amazon will display them within fifteen seconds.Likewise if some one buys a book the stock is adjusted just as fast.The smallest ranking is, books sold per hour,so can only be displayed at that speed.

Sales ranking is exactly that,the number of units sold.Amazon do list books, not in stock and never sold.

stephenf said:

The figures shown are Amazon's ,not made up by me.It is out-of-date but the principle remains true. If you have some statistics that prove the graft to be wrong, pleas post them,or are you just expressing a personal opinion?

Click to expand...

Where did you get this table?

Just curious...

stephenf said:

The figures shown are Amazon's ,not made up by me.It is out-of-date but the principle remains true. If you have some statistics that prove the graft to be wrong, pleas post them,or are you just expressing a personal opinion?

Amazon operate in real time.If a book seller adds books to Amazon stock
of books, Amazon will display them within fifteen seconds.Likewise if some one buys a book the stock is adjusted just as fast.The smallest ranking is, books sold per hour,so can only be displayed at that speed.

Sales ranking is exactly that,the number of units sold.Amazon do list books, not in stock and never sold.

Click to expand...

I know from watching my own books. I don't have a graph to prove it. Fifteen seconds? Haha! I wish. DTP takes two days to get everything up on an ebook listed.

Real time? No. Buy a book and watch it for a couple hours. The rankings will take at least an hour to reflect the purchase (sometimes the rankings drop before then because the new purchase hasn't registered yet and the book has been slow in sales).

Number of units sold? No. Rankings are a reflection of the acceleration of a books sales relative to all other books in its store. I've learned how Amazon rankings work from personal experience and watching my books and discussing this topic many times with other authors.

Sure, they list books not in stock and never sold. I won't argue that.

Amazon Sales Ranking

We have a book on Amazon that has ranked as high as 63,000 and as low as 800,000 and we have sold about 15 books a months since it was published July 2010. So I am not sure how accurate this is. Last I looked the book was ranked at about 100,000.

I Kindle ranking on amazon was as high as 8000 and as low as I think 50000 out of 700,000 kindles and we have had steady sales of about 30 a month since July 2010.

stephenf said:

Amazon adjusts it sales ranking in real time. It is a complex system ,and amazon make adjustments, But it is roughly this

Rank Copies sold/per day

1............ 3000
10........... 650
100..........100
1000.........13
10,000...... 2,2(11 copies every 5 days)
1,000,000.. 0,0006(3 copies every 500 day)

Obviously ,there are ranking numbers in between and I have seen books ranked over 4,000,000,which probably means, never been sold on Amazon.

Click to expand...

I think once it gets over a particular number (like 200k - 300k?) that it doesn't recalculate on a daily basis, but every few days or every week.

If you're over a million, I read somewhere that it doesn't recalculate those except on a monthly basis. Which is why you can be 2 million in rankings, and then jump all the way down to 100k the next day (which I have seen happen with my books).

Questions about Amazon's ranking system

James D. Macdonald said:

His book went up on Kindle on May 12, 2011, and it has an Amazon rank of #85,422 Paid in Kindle Store.

That means one download.

Click to expand...

What's the formula between Amazon rankings for ebooks and Kindle downloads? Is it possible to figure out how many copies of a book has sold based on its current Amazon ranking? And does that ranking change every hour, every 3 hours, every day ... every minute?

Someone on a FB writer's group said they were ranked #1 in childrens books but didn't say for how long - and by the time I read the post a few hours later the book had dropped down - so what does that achievement actually mean?

juniper said:

What's the formula between Amazon rankings for ebooks and Kindle downloads?

Click to expand...

Amazon has a decaying average. And, the ranks are relative; a book in a category where the other sales are dismal will rank high, even though its own sales are only slightly less dismal.

I base my estimate on one of my own Kindle downloadable works, which had one download, and ranked about that same level three days after it had been uploaded.

If the top sellers have a bad day for some reason, your own book can jump up a thousand places in the main bookstore, even without selling a single copy.

While Kindle=kindle, and Amazon is about the only place to get them, Amazon numbers are even more unreliable for non-electronic books. All they report are sales through Amazon, which is a dipstick, not an absolute measure.

Even Bookscan, which covers around 60% of book sales, is inexact and can lead you into error. A book that's selling well at Amazon is generally selling well elsewhere. The converse is not true.

Being ranked #1 in some category or another is easily gamed; it means precisely nothing.

stephenf said:

Amazon operate in real time.If a book seller adds books to Amazon stock
of books, Amazon will display them within fifteen seconds.Likewise if some one buys a book the stock is adjusted just as fast.The smallest ranking is, books sold per hour,so can only be displayed at that speed.

Sales ranking is exactly that,the number of units sold.Amazon do list books, not in stock and never sold.

Click to expand...

Over the years I've tried to find out their formula, but with no success. From the little I've lerned, the above appears to be true. But what about their used and/or out of print books? Does the same formula apply?

I think those numbers Stephen posted are dramatically off, for a couple of reasons.

Reason #1: Like James pointed out, ranking adjusts by sales velocity, not just raw sales. So if your book has been hovering at say a 10k ranking for the last two weeks, you can *roughly* compare it to another book that's been hovering at the same ranking for an extended period of time. But most books don't sit still like that, which makes it very hard to judge.

Reason #2: Those numbers change, a TON, based on current velocity of sales. For instance, in late Feb or early March Locke reported that the #1 seat resulted in over 5000 sales a day, every day, for the period he held it. Does #1 rank still do that much, or was that just his book? Does it do MORE now, because more people are reading ebooks than were in March? One book at the top seat might be selling 10k a day; another might be selling only 3k a day, and bump down fast. Really hard to say.

Reason #3: The numbers all seem very low to me. In fact, across the board they are lower than every reported ebook sale I've seen, including my own. A 10k rank seems to be something more like 10 books a day, right now, and rank 1000-ish has been holding at about 50-60 books a day for a few weeks now (gradual upward trend). That's based on real observations of books actually for sale, by myself or other writers I correspond with on the subject. But again - that's not perfect - because it's about velocity, and rank decays over time, so a big one day boost of 500 sales might kick you up very high, and even at one sale a day afterward, you will still only slide down in the rankings over a period of weeks.

I can tell you from my own experience that selling at a rate of 17 a day was enough to be just outside the top 5000.

Also, it's definitely not real time. A sale takes an hour or two to show up on your figures (mine anyway), and than another hour or two to affect your ranking.

Jim's right about the genre lists, it takes little to crack them, especially on a one-off basis.

According to all of you my sales stink

Meh, I ain't dead yet. I'm just getting started

dgaughran said:

I can tell you from my own experience that selling at a rate of 17 a day was enough to be just outside the top 5000..

Click to expand...

I think a lot depends on genre too. I've seen one of my ebooks sit at around 1000 for a week and only had maybe three or four downloads a day during that time.

Another book has been selling more steadily, but is struggling to stay around the 10k mark.

stephenf said:

Amazon adjusts it sales ranking in real time. It is a complex system ,and amazon make adjustments, But it is roughly this

Rank Copies sold/per day

1............ 3000
10........... 650
100..........100
1000.........13
10,000...... 2,2(11 copies every 5 days)
1,000,000.. 0,0006(3 copies every 500 day)

Click to expand...

3000 a day! Hot damn. That would be so freaking cool!

Ok, so math isn't my strong suit. Making the leap from 10,000 to 1,000,000 - I can't fill in the gaps.

If a book is ranked at 100,000, how many units sold?
If a book is ranked at 200,000, how many units sold?

Roughly, I mean. Approximates are just fine.

juniper said:

Ok, so math isn't my strong suit. Making the leap from 10,000 to 1,000,000 - I can't fill in the gaps.

If a book is ranked at 100,000, how many units sold?
If a book is ranked at 200,000, how many units sold?

Roughly, I mean. Approximates are just fine.

Click to expand...

There aren't a million ebooks on Amazon yet, so it doesn't go that high.

Down at 100k and below, the sales are...very low. I don't have hard current data, but we're talking "a few sales a month" sort of low.

OK, here's an idea for an approximate. Dean Wesley Smith said in Dec. that his short stories avg something like 10 sales a month over all sites, mostly from Kindle. Most of his shorts are in the 200k-400k rank range. So figure something like 4-6 sales a month in that range...?

But that data is months old. Overall Kindle sales are increasing every month; and that means the numbers sold at every point of the scale are trending upward month by month as well. Unfortunately, the sales figures are such a moving target right now that by the time anyone could compile data and publish it, the data would probably already be out of date!

I just checked. My book HATCHINGS currently ranks at #44,344 with sales of 2 books since it went live on the 6th of this month (05/06/11). That's about where it debuted BTW. I highly suspect the sales figures are low and slowly reported and do not reflect an accurate day-to-day sales figure. Amazon reports that it updates as of the 15th of the month and between the 1st and the 15th I can tell you with experience since February that the actual sales numbers don't change much between those dates.

Your experience may differ, of course.



It was up around 185k yesterday at this time.

And in the time it took me to write the previous post, re-check, and write this one HATCHINGS dropped to #48,184.