Publishing math, worked out plainly

Publishing calculators for indie authors.

Royalties, print costs, page counts, trim sizes, and profit — a growing set of focused publishing calculators, no signup, no dashboard to learn.

Tool clusters

What PublishCalc helps you calculate.

Ten tools, organized into three groups so you can go straight to the kind of decision you're making.

Pricing & royalties

Royalty, break-even price, pricing scenarios, KENP earnings.

Start with royalty

Print & production

Print cost, trim size guide, spine width, cover dimensions.

Start with print cost

Manuscript planning & profit

Word count to page count, and book profit projection across your catalogue.

Start with word count
Next decisions

Publishing math follows a natural order.

Most authors move through these questions in roughly this sequence — each tool links to the next one.

Typical planning pathManuscript → Profit
1. Manuscript word countWord → pages →
3. Spine widthSpine width →
4. Print costPrint cost →
5. Pricing strategyBreak-even price →
6. Royalty per saleRoyalty →
7. Catalogue profitProfit projection →
Why authors use this

Built for the ten minutes before you hit publish.

Most self-publishing decisions come down to a handful of numbers: what a book should cost, what it will actually earn, and whether the economics hold up across a catalogue. PublishCalc exists to answer those questions quickly, without an account or a walkthrough.

  • No signup, runs in your browser. Every calculation happens on the page. Nothing you type is sent anywhere.
  • Estimates, labelled as estimates. We show the assumptions behind every number so you know exactly what's modeled.
  • A growing set of tools, tightly linked. Your word count feeds page count, page count feeds spine width and print cost, and royalty feeds profit projection.
How the estimates work

Transparent formulas, editable assumptions.

Each calculator uses a documented formula built from publicly discussed publishing-industry planning figures — royalty percentage bands, per-page print cost, and pages-per-inch for spine width. None of it is pulled live from a publishing platform, and we say so on every results page.

Rates and print costs are set by the platform you actually publish through, and they change over time. Treat every number on this site as a planning estimate to sanity-check your pricing, not a guarantee of what you'll be paid.

Read the full FAQ
Sample estimatePaperback
List price$14.99
Estimated print cost−$3.42
Modeled royalty rate60%
Estimated royalty / sale$5.57
Frequently asked

A few things worth knowing before you rely on these numbers.

Are these royalty numbers exact?

No. They're modeled estimates built from publicly discussed royalty percentage bands and a print-cost formula. Your publishing platform's live rates are the source of truth — use these numbers for planning, then confirm final pricing on the platform itself.

Why does print cost change by marketplace?

Printing happens at regional print facilities, and both base cost and per-page cost differ by currency and region. That's why every print-related calculator on this site asks which marketplace you're pricing for.

Is a spine width estimate final before formatting?

No — spine width depends on your final formatted page count, paper type, and binding, so treat the estimate as a planning figure for cover design, then confirm it once your interior file is finished.

See all FAQ questions →

More calculators are on the way.

We're keeping the launch set narrow on purpose. If you'd like a note when new planning tools ship, there's no list to join yet — just bookmark the site.

Start with royalties