Skip to content
Cover of Mostly Harmless by Douglas Adams

Book · Fantasy and science fiction

Mostly Harmless

by Douglas Adams

Page count, estimated reading time and reading quiz: everything to know before you start Mostly Harmless, and the Vread challenge to get to the end.

Pages
250
Reading time
≈ 4 h 30 min
Checkpoints
7
Genre
Fantasy, SF
Take the challengeAlready have the app? Open the book

Free on iPhone and Android.

How long does it take to read Mostly Harmless?

At 250 pages, Mostly Harmless is a medium-length book. Expect about 4 hours 30 minutes of reading to finish it, based on 250 words per page and an average reading speed of 230 words per minute. A fast reader will go quicker; a careful read (or reading in a second language) will take longer.

At 30 minutes a day, that is about 10 days of reading. At the median pace of Vread readers, 72 pages per reading day, it takes 4 reading days. For a book of this length (250 to 399 pages), Vread readers who finish it take a median of 4.7 days between the first and the last checkpoint (Vread Reading Barometer 2026).

Reading days to finish it
30 minutes a day10 days
Vread median pace (72 pp./day)4 days

Estimates; see the method at the bottom of the page.

Prove you read it

The Vread challenge: 7 checkpoints

  1. Checkpoint 1, page 36
  2. Checkpoint 2, page 71
  3. Checkpoint 3, page 107
  4. Checkpoint 4, page 143
  5. Checkpoint 5, page 179
  6. Checkpoint 6, page 214
  7. Checkpoint 7, page 250

In Vread, Mostly Harmless is split into 7 checkpoints, one every 36 pages or so. At each checkpoint, a question covers the passage you have just read: a correct answer validates the step, and your progress moves forward like a training plan.

The challenge: validate all 7 checkpoints through to the last page. No giant quiz at the end, no summary to copy out: short questions along the way that prove the book was actually read. It also works as a reading quiz to check your understanding before a test.

Also available in French on Vread.

Illustrative example

Checkpoint 1/7pp. 1–36

What a checkpoint looks like

A short, precise question about the pages you have just read: a character, a place, a choice.

The answer is in the text: reply in the app.

This is not a question from Mostly Harmless: to avoid spoilers, the real questions stay in the app.

Answer in the app, one checkpoint at a time.

Summary, quiz, reviews: frequently asked questions

How many pages is Mostly Harmless?
The edition listed on Vread has 250 pages. The exact count varies by edition (paperback, hardback, ebook).
How long does it take to read Mostly Harmless?
About 4 hours 30 minutes of reading, or 10 days at 30 minutes a day.
Is there a quiz on Mostly Harmless?
Yes: the Vread app has 7 reading questions on Mostly Harmless, one per checkpoint, unlocked as you read.
Where can I find a summary of Mostly Harmless?
Vread does not publish summaries: the app supports reading the book itself, part by part. Checkpoint questions cover what you have just read, which makes them a good way to check you did not miss anything.

Similar books: fantasy and science fiction

All books: fantasy and science fictionAll genres

Read Mostly Harmless with Vread

Add the book to your library, read at your own pace in whatever format you use, and validate each checkpoint. Vread is free on iPhone and Android.

Take the challenge

Written by Vread from its catalogue data (page count of the listed edition, checkpoints, ratings aggregated from 10 ratings). No summary or publisher text is reproduced. Reading times are estimates; see the method in the Vread Reading Barometer (in French).