Quick answer: Christian Author Demand Lab is the research app I’ve built for Christian indie authors. It pulls live data from Amazon, Google, and short-form video so you can check if readers actually want your topic, see how many daily sales it takes to rank in a category, look under the hood of a bestseller, and shape your title before you write chapter one. Access comes with a paid Christian Book Finder subscription.
Many authors spend months, or even years, writing a book only to learn an unsettling reality: not as many were as interested as they thought.
This happens to indie authors every single day. Their writing is fine, they just went into the market blind, before anyone checked whether a buying audience existed, or whether the big publishing houses already owned the topic.
That’s a lot of hours to bet on a hunch. So I built a tool that checks the hunch first. Here’s what each part of Demand Lab does, in roughly the order you’d use it.
Checking for readers before you write a single chapter
The Validate Demand tool tells you whether people are searching for your topic right now.
It pulls from three places at once. Amazon shows you buying intent, meaning people with their wallets out. Google shows curiosity, the folks typing in a problem and hoping somebody wrote a book about it. YouTube Shorts and TikTok show momentum, the topics people are talking about this month that may not have hit the bookstore yet.
You get a trend line for your topic. If it slopes up, interest is growing. You can also split the line out by channel if you want to see which platform is doing the most.
Then the tool scores your topic on three 0–100 scales. Demand is how much interest exists overall, where 0 means almost nobody is looking and 100 is peak demand. Competition is how crowded the shelf already is. Momentum is whether the topic is gaining steam or fading out.
Read those scores together. A high demand score sitting next to a high competition score means readers want it, but so does every other author — you’ll need a sharper angle to get noticed.
That’s where the related topics and reader struggles come in. The tool lists both under your results, and clicking any one of them runs a fresh search on it. So a broad idea like “prayer” can narrow down, a click at a time, to the specific problem a specific reader is trying to solve.
Validate Demand at a glance:
Sources — Amazon, Google, YouTube Shorts, TikTok
Demand score — 0 to 100, overall reader interest
Competition score — 0 to 100, how crowded the topic is
Momentum score — 0 to 100, rising or fading
Related topics and struggles — one click runs a new search
How many sales it takes to rank in a category
Category Search shows you the actual sales numbers behind an Amazon category, so you can pick ones you have a real shot at.
A lot of authors will pick categories by how they sound. “Ministry & Evangelism” sounds right for a church outreach book, so in it goes. But ranking in a category is a numbers game, and Category Search puts the numbers in front of you.
For any category you open, you’ll see four things. The estimated daily sales it takes to hit #1. The estimated daily sales it takes to land in the top 10. The share of top books that come from traditional publishers. And the share of top books enrolled in Kindle Unlimited.
The #1 and #10 numbers tell you how hard the climb is. If the #10 spot needs more sales a day than you can realistically drive at launch, that category will bury you, no matter how well it fits the book.
The publisher percentage tells you who you’re up against. When most of the top books come from big houses, you’re competing with their marketing budgets and bookstore deals. That’s your cue to look for a tighter subcategory.
The KU percentage tells you how readers in that category buy. A high number means they’re reading through their subscription, and you get paid by page reads. That should shape your price and whether you enroll in KDP Select.
One more thing: your category picks sit on the left, and matching keywords for KDP’s backend boxes sit on the right. So your categories and keywords point Amazon in the same direction from day one.
Category Search at a glance:
#1 daily sales — estimated sales a day to top the category
#10 daily sales — estimated sales a day for a top-10 spot
Publisher % — share of top books from traditional houses
KU % — share of top books in Kindle Unlimited
Keyword pairing — backend keywords matched to your categories
Seeing the search terms behind a bestseller
Reverse ASIN Search shows you which Amazon searches a competing book shows up for.
First you need the book’s ASIN (or ISBN). You’ll find it in the product details section of the Amazon page. Or look at the book’s web address — it’s the string of letters and numbers right after /dp/.
Paste that in, and the tool pulls up the search terms the book ranks for. Try it on a proven bestseller like The Awe of God and you’ll see what shoppers type in to find it.
Each search term comes with three numbers. A competition score from 0 (easy to rank for) to 100 (good luck). An estimate of how many people search that exact phrase on Amazon every month. And the estimated average monthly earnings of the top books in those results.
The last number is the one I’d watch. A search term with decent monthly searches, a moderate competition score, and healthy average earnings is a term worth building your book around.
Now, I will say, Demand Lab is a research tool. It won’t guarantee you sales, and it won’t guarantee you a category ranking. What it does is raise your odds, because you’re making decisions off live Amazon data instead of a gut feeling.
Reverse ASIN Search at a glance:
Finding the ASIN — product details, or the code after /dp/ in the URL
Competition score — 0 to 100, how hard the term is to rank for
Searches per month — estimated Amazon searches for that exact phrase
Average sales — estimated monthly earnings of top books for that term
Finding your angle and the words buyers type
Demand Scout helps you find the angle the bestsellers missed, and Keyword Lab turns that angle into a title and keywords Amazon can use.
A book has to win twice to sell. Amazon’s search has to surface it, and then a real person has to click on it. These two tools handle one win each.
Demand Scout lays out the bestsellers for your topic side by side: Best Sellers Rank, estimated monthly royalties, page count, and list price. Then hit Analyze Competitive Advantage. It compares your book idea against the current leaders and points out the gaps none of them are covering. You can pick one of the suggested angles or type in your own, and the tool shapes it into a clear spot in the market for your book.
Once you know your angle, Keyword Lab fills in the seven backend keyword slots KDP gives you. It finds the phrases real buyers are typing, then writes title and subtitle options built around those phrases.
The keywords are for Amazon’s algorithm, so your book shows up in the right searches. The title and subtitle are for the human scrolling past, so they know in two seconds what your book does for them. You need both.
Positioning tools at a glance:
Demand Scout — compares bestsellers by BSR, royalties, page count, and price
Analyze Competitive Advantage — finds gaps between your idea and the leaders
Keyword Lab — fills all 7 KDP backend keyword slots
Title and subtitle options — built from what buyers actually search
Launch timing and formatting, off your plate
Two more tools handle the parts of launching that have nothing to do with writing and everything to do with getting stuck.
The Launch Calendar is a VIP feature. It reads the research reports you’ve saved and suggests publication dates that fit your genre, with plans for both a standard launch and a pre-launch. Alongside it, Find My Best Launch Day and Find My Best Promo Window walk you through a few questions, then tell you when to release and when to run your price drops and promos. Your first few weeks set the tone with Amazon, so timing matters more than most authors think.
The Manuscript Formatter is 98% finished. Formatting mistakes delay launches and make books look sloppy on a Kindle or in a print proof. Here’s what it does:
Builds your front and back matter for you — title page, copyright page, table of contents, dedication….etc. Click “looks right” to approve a section, or rename it, edit the text, and merge or split sections.
Sets your trim size, with 6 × 9 as the default. Most of the authors I work with pick a 6 × 9 paperback and would rather have a thinner book than a smaller one.
Applies a design style: Classic, Devotional, or Modern.
Lets you keep or remove images and choose justified, left-aligned, or centered text.
Exports a clean file ready for KDP upload.
Launch and formatting tools at a glance:
Launch Calendar (VIP) — genre-based release dates from your saved research
Find My Best Launch Day — guided pick for release day
Find My Best Promo Window — when to run discounts and promos
Manuscript Formatter — 98% complete, 6 × 9 default, KDP-ready export
Where to start
So what would change if your next book topic had real reader data behind it before you wrote the first word? You’d stop guessing which idea to chase, and you’d spend those six months on a book people are already looking for.
Here’s the order I’d go in. Take the book idea you’re most excited about and run it through Validate Demand. If the scores hold up, open Category Search and find two or three categories where the #10 spot is within reach. Then use Reverse ASIN Search and Demand Scout to see what the leaders are doing and where they left a gap. Finish in Keyword Lab with your seven keywords and a title that says what your book does.
“The plans of the diligent lead surely to abundance.” — Proverbs 21:5
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