Self-publishing arithmetic: page counts, reading and audiobook time, spine and cover size, trim sizes, royalties and ebook size.
payments ON MAINNET (real money) · 9 live endpoints
| Endpoint | Price | What it answers |
|---|---|---|
GET /audiobook-length | $0.02 | Audiobook running time from a word count at about 9,300 words per hour (change it), as hours and clock time. |
GET /chapter-balance | $0.02 | Split a total word count into N balanced chapters with exact per-chapter words, pages and reading minutes. |
GET /cover-size | $0.02 | Full paperback cover width and height with bleed from trim size and page count, in inches, mm and pixels. |
GET /ebook-size | $0.02 | Estimate ebook file size in KB and MB from word count, image count and average image size (all adjustable). |
GET /page-count | $0.02 | Pages from a word count at your words-per-page figure, rounded up, plus even page count and sheets for print. |
GET /print-royalty | $0.02 | Print book royalty per copy from list price, printing cost and royalty rate, plus break-even price and total. |
GET /reading-time | $0.02 | Silent reading time for a word count at your words-per-minute (default 238), as minutes and hours:minutes:seconds. |
GET /spine-width | $0.02 | Print book spine width in inches and mm from page count and paper type (white, cream, color) or your own thickness. |
GET /trim-sizes | $0.02 | Standard US trade book trim sizes in inches and mm, or look up one size like 6x9 and its closest standard. |
GET /catalog returns this list as JSON. Activity hub · uptime.
Self-publishing arithmetic computed locally from the numbers you give. Paper thickness, words per page and narration pace are common published figures that vary by printer, typeface and narrator: check your printer's own cover template and royalty calculator before ordering. Not legal, tax or financial advice. Every paid response carries a disclaimer field.