A novella is a work of prose fiction roughly between 17,500 and 40,000 words — long enough to carry a real arc, short enough to be read in one or two sittings. The numbers vary by who you ask, and they matter mostly to competitions and publishers. What matters to a reader is the shape, and the shape is genuinely different from a novel.
A novel can afford detours. A short story cannot afford a second thread. A novella gets one idea and follows it all the way down.
The lengths, roughly
Short story — under about 7,500 words. Novelette — roughly 7,500 to 17,500, a label you will mostly meet in science fiction and fantasy awards. Novella — roughly 17,500 to 40,000. Novel — 40,000 and up, with most published fiction landing between 70,000 and 120,000.
Treat these as road signs, not laws. A 45,000-word book is often sold as a short novel and a 38,000-word book as a novella, and nobody is being dishonest. If you are trying to work out where your own draft sits, how many words is a novel goes through the ranges by genre.
What actually makes it a novella
Length is the symptom; concentration is the cause. A novella typically has one central question and refuses to be distracted from it. Subplots are rare. The cast is small, often three or four people who matter. The timeframe is usually tight — a week, a journey, a season.
The other defining trait is that there is nowhere to hide. A novel can carry a weak chapter; the reader is a hundred pages in and will forgive it. In a novella a weak chapter is ten percent of the book. Every scene has to do at least two jobs, which is why the form has a reputation for being harder to write than its length suggests.
And the ending arrives at speed. Novellas tend to tighten rather than resolve — they end on the sharpest possible point rather than winding down through an epilogue.
Why writers choose it
Sometimes the idea is simply novella-sized. A single moral dilemma, one relationship under pressure, one transformation. Padding that to 90,000 words would not make it better; it would make it slack. Recognising that an idea has a natural length is a real skill and saves months of work.
It is also an excellent form for a first finished project. Forty thousand words is achievable, and finishing something teaches you things that abandoning three novels never will — the argument we make in how to write a book with no experience.
The honest catch: novellas have historically been awkward to sell as single printed books, which is why so many appear in collections or paired together. Online that constraint mostly disappears, since nothing has to justify a spine width.
Where to start reading
Several of the most famous works in the language are novellas, which tells you something about the form. The Metamorphosis by Franz Kafka — one premise, followed without flinching. The Strange Case of Dr Jekyll and Mr Hyde by Robert Louis Stevenson. Heart of Darkness by Joseph Conrad. A Christmas Carol by Charles Dickens — four spirits, one night, no slack. The Turn of the Screw by Henry James, if you like being unsure what you just read. All of those are out of copyright; free public-domain classics covers where to get decent editions rather than bad scans.
More recent ones worth knowing: Of Mice and Men by John Steinbeck, The Old Man and the Sea by Ernest Hemingway, and Animal Farm by George Orwell — all short, all doing more than most novels three times their size.
The novella as a cure
If you have not finished a book in two months, a novella is the obvious move. One or two sittings, a complete experience, and the feeling of having read something all the way through — which is usually what restarts a reading habit. That is the logic behind short books to beat a reading slump, and the novella is the sweet spot of that list: short enough to finish, long enough to count.
Writing one
Pick one question and write toward it. Resist the second subplot, keep the cast small, and start as late in the story as you possibly can. If you find yourself inventing material to reach a word count, the idea was a short story; if you keep discovering necessary threads, it was a novel.
A novella also sits well in instalments — ten to fifteen chapters is a natural serial, which is the rhythm serialised fiction describes. That is what Arwy, the Android reading and writing app we make, is built around: you publish chapter by chapter and readers can respond while you are still writing. If what you want is a printed novella you can hold, we are the wrong tool entirely — that is a job for a print-on-demand service.
Reading something short and sharp right now? Find someone else in it. Arwy is on Google Play.