Reading time calculator
How long will this book take you?
A free book reading time calculator that works in pages, not word counts. Give it the page count and your own pages per hour — it returns the hours, and what that means on the days you actually read.
After the estimate
Don't guess your reading pace. Measure it.
One sitting told you a number. A hundred of them tell you something steadier. RUNU works your pages per hour out from sessions that recorded both a duration and the pages you advanced — and shows nothing at all until one has.
RUNU is in pre-launch. This page doesn't know your account, doesn't read your session history, and nothing you type here is saved.
How the calculation works
Three divisions, all of which you can check by hand.
How to calculate your reading pace
pages per hour = pages read ÷ (minutes ÷ 60)
32 pages in 48 minutes is 32 ÷ 0.8 = 40 pages an hour. One sitting is enough to get a usable figure; it needs both a real duration and the pages you actually moved through.
How to calculate reading time for a book
hours = pages in the book ÷ pages per hour
420 ÷ 40 = 10.5 hours, shown as 10h 30m because nobody thinks in tenths of an hour. No word count, no words per page, no assumed reading speed enters this sum.
How many days to finish a book
days = total minutes ÷ minutes you read a day
630 ÷ 30 = 21 days. Those are reading days — days you actually open the book. Skip two and it's 21 reading days spread across 23.
Pages per hour vs words per minute
Words per minute is the standard for articles, where the word count is known exactly. A book gives you pages, not words — so converting to WPM means guessing at words per page, and that guess is doing all the work. Pages an hour skips the guess: it is measured on the same unit the book is printed in.
Why pace moves between books
Page size, type size, leading, density and difficulty all differ. A dense 300-page history and an airy 300-page novel are not the same 300 pages. Read the result as "at this pace", not as a permanent speed.
Worked example
One session, one book, one answer.
Illustrative numbers, chosen because they divide cleanly — not a real book or a real reader. Every figure below is the previous one divided by something.
Step one — the session
32 pages in 48 min
48 minutes is 0.8 of an hour. 32 ÷ 0.8 = 40 pages an hour.
Step two — the book
420 pages ÷ 40
= 10.5 hours, written as 10h 30m, or 630 minutes of reading.
Step three — the days
630 ÷ 30 = 21
Half an hour a day finishes it in about 21 reading days. An hour a day: 630 ÷ 60 = 10.5, so 11 days.
Reading pace changes from book to book. Treat this as a useful estimate, not a deadline.
Questions
Reading time, answered plainly.
How long does it take to read a book?
Divide the page count by your pages per hour. A 420-page book at 40 pages an hour takes 10.5 hours — 10h 30m. The page count is a fact about the book; the pace is a fact about you, and it's the half of the sum most calculators invent on your behalf.
How do I calculate my reading pace?
Time one sitting and note the pages you advanced, then divide: pages ÷ (minutes ÷ 60). 32 pages in 48 minutes is 40 pages an hour. Anything shorter than a few minutes is mostly noise — a session needs both a real duration and a real page movement to say anything.
What if I don't know my reading speed?
Use the session calculator above — one remembered sitting is enough. If you don't have even that, the estimate bands will fill the field with a rough figure, and the result stays labelled as an estimate until you replace it with something measured. An estimated pace is a placeholder, not a fact about you.
How many pages per hour should I read?
There's no target worth hitting. Pages an hour is a measurement, not a score, and pushing it up mostly means remembering less. The useful thing it gives you is planning: how long a book will take, and whether the evening you have is enough for the chapter you want.
Why does my reading pace change between books?
Because a page isn't a standard unit. Trim size, type size, leading and word density vary widely, and so does difficulty — a page of dense argument and a page of dialogue take different amounts of you. Expect the figure to move, and read every result here as "at this pace".
Can RUNU measure my reading pace?
RUNU works out pages per hour from your recorded reading sessions — the ones that captured both a duration and the pages you advanced. Sessions without one or the other are simply left out of it, so the figure never quietly drifts toward zero. This calculator, though, is a public page: it uses only what you type into it, and knows nothing about any RUNU account.
Your pace is one reading statistic among many. Reading statistics is where the rest of them live.
Turn reading time into reading history.
The estimate was free. What it's estimating — your sittings, your pace, the pages behind you — is what RUNU is for. A personal reading tracker, currently in pre-launch.
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