Pinning down a strict word count for novellas is notoriously slippery, partly because different literary traditions and award bodies draw their own lines. The Science Fiction & Fantasy Writers of America, for instance, sets the Hugo Award category for novella at 17,500 to 40,000 words. I’ve always used that as a baseline for speculative fiction. But in mainstream literary circles, I’ve seen editors and presses accept works up to 50,000 words under the novella umbrella, which starts to bleed into short novel territory. The fuzziness is real. I think the definition matters less than the inherent structure; a novella feels like a single, sustained breath, a story that can’t be a novel but demands more space than a short story allows.
That said, if you’re submitting your work, you absolutely need to check the specific guidelines of the publisher or contest. A 45,000-word manuscript might be a novella for one imprint and a short novel for another. For readers, the practical impact is just knowing you’re in for a one or two-sitting commitment, a deeply focused narrative without the sprawl of subplots. Classics like 'The Metamorphosis' or contemporary works like Ted Chiang's 'Story of Your Life' live in that sweet spot where every word carries immense weight.