Those interested in locating a digital version of Marx’s Capital, Volume I may be interested to learn that a scanned copy of the 1976 Ben Fowkes translation published by Penguin (now Penguin Random House—Marx called this process the centralization of capital) is available for download and in-browser reading in the Internet Archive. At the time it appeared, Raya Dunayevskaya hailed it as “a more accurate and beautiful translation” and it still remains the best English-language version available. This, despite the fact that it is burdened with a long introduction by the late Trotskyist Ernest Mandel that Dunayevskaya characterized as an “utter perversion” in her critique, “Today’s Epigones Who Try to Truncate Marx’s Capital.” An excerpt from her critique is available in the Marxist Internet Archive. The full text can be found in Marx’s Capital and Today’s Global Crisis.
Mandel aside, the Penguin edition has the merit of including Results of the Immediate Process of Production, often described as the original concluding chapter of Capital. This text contains Marx’s important discussion of the concepts of the real and formal subsumption of capital.
Readers of the Fowkes translation should be aware of the fact that, although it incorporates some of the text from the 1875 French edition of Capital, held in high esteem by Marx and described by him as “possess[ing] a scientific value independent of the original,” it adheres closely to the fourth German edition as represented by the Marx-Engels Werke text. Dunayevskaya drew attention to the significance of the French edition of Capital in Rosa Luxemburg, Womens’ Liberation, and Marx’s Philosophy of Revolution. For a close examination of the Fowkes translation versus the French edition, see Kevin Anderson’s “The Unknown Marx’s Capital, Volume I: The French Edition of 1872-75, 100 Years Later” in Review of Radical Political Economics 1983, Volume 15.
The Internet Archives copy of this edition probably would not withstand a takedown challenge from Penguin Random House’s copyright lawyers, so if you’re interested in this text you should probably view it soon. An alternate translation of Vol. I, securely in the public domain and still worth consulting for its historic value, is the Charles H. Kerr edition. A scanned version of the Library of Congress’s copy is also available in the IA.