After dinner in Richmond, the Time Traveller, whom Wells never names, sets a small ivory-and-crystal machine on the table and it disappears. A week later he limps in halfway through his own dinner party, filthy and grey, and tells the rest of the book: the year 802,701, where leisure and labour have bred humanity into two species, the small idle Eloi in the gardens above and the pale Morlocks working the machinery below. His machine goes missing. A small Eloi called Weena attaches herself to him. Then further out still, to giant crabs on a beach under a swollen red sun. Be ready for a monologue: four-fifths of this is one man talking after dinner, and its longest chapter breaks off to explain the theory.
The Time Machine is 32,463 words. At an average adult reading pace of 300 words a minute that is about 1 hr 48 min, or roughly 1 hr 21 min if you read quickly and 2 hr 42 min at a more deliberate 200 words a minute.
That count is measured from the complete public-domain text rather than estimated from a page count, so you can compare all the books side by side.