Research
How many braille pages will my book be?
Every result for this question is a transcription vendor quoting three to four pages per print page and asking for the file. Here is the arithmetic.
The rule of thumb is not wrong, exactly. It is just an answer to a question nobody asked in those terms, wrapped around the one number that actually varies — how full the print page was — without saying so.
The real question has a real answer, and it does not need a quote. It needs a page size, a piece of text, and a layout engine that lays the text out instead of dividing.
Why dividing does not work
The obvious method is to translate the text, count the cells, and divide by how many cells a page holds. It is obvious, it is arithmetic, and it is wrong by a wide margin, because braille does not reflow the way a screen does.
A braille line stops at the last whole word that fits and wastes the cells between there and the margin. Every paragraph opens two cells in. A running head takes a line off every page. None of that survives a division.
| Method | Lines | Pages | Against the real figure |
|---|---|---|---|
| Cells divided by line length | 2,146 | 89 | 34.7% short |
| Cells plus the spaces between words | 2,807 | 117 | 14.6% short |
| Laying the text out | 3,272 | 137 | — |
Both shortcuts undercount, and the better of the two is still 14.6% short. On a novel that is 20 pages of braille nobody budgeted for.
The method
- Question
- How many braille pages does a given amount of English prose become?
- Compared against
- Nothing — this is a measurement, not a comparison. The page follows the BANA Braille Formats defaults: 40 cells by 25 lines, one line given to a running head, paragraphs indented two cells.
- Over
- The body text of Alice’s Adventures in Wonderland, body text — 26,439 words, 143,942 characters of ordinary narrative English.
- Committed as
forge/topics/braille/data/prose-sample.txt
One book is enough because the figures it yields are within three per cent of the same measurement over two other novels. Ordinary narrative prose is consistent in the way that matters here — average word length and paragraph frequency — and those are the two things the layout is sensitive to.
The result
| Grade 1 | Grade 2 | |
|---|---|---|
| Words | 26,439 | 26,439 |
| Cells | 120,461 | 85,831 |
| Lines | 4,214 | 3,272 |
| Pages | 176 | 137 |
| Words per page | 150 | 193 |
| Cells per word | 4.56 | 3.25 |
So a page of contracted braille holds about 193 words of ordinary English, and an uncontracted one about 150. Multiply your word count by 0.1238 to get lines, divide by 24 to get pages — or paste the text into the estimator, which lays it out properly.
What Grade 2 actually saves
Contracted braille is usually described as saving about a quarter to a third, which is true of cells and not of paper.
| In | Saving |
|---|---|
| Cells | 28.7% |
| Lines | 22.4% |
| Pages | 22.2% |
The saving in cells is larger than the saving in paper, and the gap is the line-end waste. Shortening the words does not shorten the ragged edge at the end of every line — if anything it leaves slightly more of it, because a shorter word is likelier to fit in a gap the previous line could not use.
That gap is 6.6 percentage points between what the contractions do to the text and what they do to the shelf. Grade 1 versus Grade 2 covers when the trade is worth making at all.
Where the vendors' three-to-four comes from
A print page is not a fixed amount of text. A double-spaced manuscript page runs about 250 words; a trade paperback 275; a mass-market paperback 325. At those densities the ratio is nowhere near three.
The rule of thumb holds at about 700 words to the print page — a dense, small-type or double-column setting. It is a real number for the documents the transcription trade mostly sees, and a misleading one for a novel.
| Print page | Words | Braille pages per print page |
|---|---|---|
| Manuscript, double spaced | 250 | 1.3 |
| Trade paperback | 275 | 1.4 |
| Mass-market paperback | 325 | 1.7 |
| Dense or double column | 700 | 3.6 |
The estimator takes a print-page count directly and lets you change the assumption, because it is the one number in this that is genuinely yours and not braille's. The other measurements cover the reference tables, contraction positions and shortform endings.
What this cannot tell you
- Volumes. A braille book is bound in volumes of a manageable thickness, and the formats standard requires a volume to end at a logical break in the content rather than at a page count. Where those breaks fall is a property of your document, not of braille.
- Anything that is not prose. Tables, poetry, drama, textbooks and anything with numbered exercises carry formatting rules that change the line count substantially. This measurement is narrative paragraphs.
- Transcriber's notes and apparatus. A real transcription adds a title page, a transcriber's note, page-change indicators and often a contents list. None of that is in the text you hand over.
The finding, as a card
The number and what it is measured on, in one picture.
