When my editor sent over the production checklist, I expected to wince at the cover design line item. Instead, it was the indexing quote that stopped me cold: $900, with a three-week turnaround — and that was the mid-range estimate.
I reached out to three professional indexers. The quotes ranged from $700 to $1,200. The timelines ran from two to four weeks. Every one of them needed the final typeset PDF before they could even begin — meaning I couldn't start the clock until everything else was done.
I'm a self-published author on a lean budget. That math wasn't going to work.
What followed was 47 minutes of work, a 14-page index, and a publisher sign-off with no revision requests. Here's exactly what happened — step by step — so you can replicate it.
Why Indexing Is the Production Step Nobody Warns You About
Ask any first-time nonfiction author what they're dreading about production and they'll say editing, formatting, or cover design. Almost none of them will say indexing — until they discover it's mandatory for most nonfiction books sold to libraries, academic institutions, or traditional retail channels.
The economics are sobering. Professional indexers typically charge $2.50–$6.00 per indexable page — which, for a 280-page business book, puts you squarely in the $700–$1,680 range depending on complexity. And the timeline compounds the pain: at an industry-standard pace of 8–10 pages per hour, a 280-page manuscript represents 28–40 hours of labor. Most trade indexers quote two to three weeks minimum.
For authors publishing with a traditional press, those costs often come out of the author advance. For self-published authors funding production personally, they frequently come as a surprise after everything else has been spent.
I nearly cut the index entirely. I'm glad I didn't.
What a Professional Index Actually Does (and Why It Matters)
Before you assume any tool — AI or otherwise — can shortcut the process, it helps to understand what a good index actually accomplishes. A back-of-book index isn't a glorified keyword list. It's a reader navigation system that:
Groups related concepts under meaningful headings and subentries
Captures relationships between ideas that appear in different chapters
Double-posts key entries so readers find them regardless of how they phrase the search
Uses cross-references ("see also") to connect related terms
Follows style conventions — typically CMOS 18th edition — for alphabetization, formatting, and page ranges
This is the detail that matters when evaluating any AI-generated index: not whether it found keywords, but whether it organized them in a way that's genuinely useful to a reader hunting for a specific concept at 11pm the night before a presentation.
My 280-page business book had five interconnected frameworks, four recurring case studies, and a lot of overlapping terminology. It needed proper subentries, not a word dump.
The Workflow: What I Actually Did
I used Onomastic, an AI-powered back-of-book index generator built for authors and publishers. Here's the step-by-step breakdown.
Step 1: Upload the final PDF (2 minutes)
I uploaded the print-ready typeset PDF — 280 pages, standard 6×9 trim. I selected "Business / Self-Help" as the content category so the tool could weight industry-specific terminology appropriately.
One thing worth knowing: upload your final typeset file. If page numbers shift after you generate the index, you'll need to regenerate. I made this mistake with a chapter heading change and spent 20 minutes fixing it. Don't do what I did.
Step 2: Review and curate the extracted entities (8 minutes)
Onomastic surfaces the people, concepts, organizations, frameworks, and key terms it's identified across the manuscript before building the index. You can promote entries (increase their weight), merge duplicate variations, or remove terms you don't want indexed.
I promoted three concepts that were central to my book's core argument — the AI had correctly identified them as frequent, but I wanted to ensure they got full subentry treatment. I also merged two variations of a recurring framework name that appeared under slightly different phrasings in early vs. late chapters.
Step 3: Generate the index (4 minutes)
The full index generated in just over four minutes. Output: 312 main entries with subentries, see also cross-references, and page ranges — delivered in a two-column Word document formatted for InDesign insertion.
Step 4: Human review and editing (33 minutes)
This is where most of my time went, and I'd encourage you not to skip it. I read every single entry. My goals were: (1) verify that subentries were meaningful rather than mechanical, (2) check that cross-references pointed to genuinely related concepts, and (3) add anything the AI had missed.
I added six entries that I knew were important search terms for my target reader. I removed two entries that were too granular. I adjusted phrasing on about a dozen subentries to better reflect how my readers think about these ideas — not just how I wrote them.
Total time: 47 minutes.
The Result: What the Publisher Saw
The final index ran to 14 pages — right in the 4–6% of total page count range that professional indexers target for a business book of this length. It contained:
312 main entries spanning concepts, proper names, frameworks, and organizations
Subentries under every major concept, organized by aspect rather than just listing page numbers
See also cross-references connecting the book's five core frameworks
Double-posting of key case studies so readers could find them under both company name and topic
The publisher's editorial contact marked the index accepted without revision. That was the moment I knew the AI output, combined with a focused human review pass, had cleared the professional bar.
What This Means for Your Production Timeline and Budget
To put the numbers in plain terms:
Professional indexer: $700–$1,200, two to three weeks, requires final typeset PDF
AI indexing workflow: significantly less, 47 minutes, same final PDF requirement
The timeline difference is often what matters most. If your publisher has a 10-day window between final typeset delivery and print submission, a three-week indexing turnaround won't work. I was in exactly that situation.
If your production schedule is tight, your budget is lean, or you're not sure whether the index you'd get from a professional would justify $900 — this is worth trying before you write that check.
Try Onomastic free and generate an index from your manuscript. See what it looks like. The worst outcome is that you learn exactly what your index needs before you hand it to a professional.
