The Book of the Dead was a commercial product. Copies were written in advance by workshop scribes with blank spaces left where the owner's name and titles would be filled in on purchase, and unfilled blanks survive in finished rolls, along with names inserted in a second, cruder hand and occasional insertions of the wrong name or the wrong gender. Quality tracked price: some rolls are careless, abbreviated, or carry vignettes with no text at all, while others are among the finest painting to survive from the ancient world.
The best known is the Papyrus of Ani, made for a Theban scribe of the accounting offices around 1250 BCE and now in the British Museum. It is some twenty-three metres long and its vignettes are exceptional, which is why its version of the weighing of the heart illustrates most popular accounts of Egyptian religion.
Ani is also the source of the translation most people have read. E. A. Wallis Budge published a hieroglyphic transcription and English rendering of it in the 1890s, and because that text passed out of copyright it has been reprinted, anthologised and posted online ever since. Budge's Egyptian was already behind the scholarship of his own day and his English is deliberately archaic; Egyptologists have criticised the translation for well over a century. It remains, by a wide margin, the version in circulation. Readers who want what the spells actually say are better served by the modern translations of Raymond Faulkner or Thomas Allen, and by remembering that the papyrus they are reading is one man's selection rather than a scripture.