Fact-checking your own book
A publishing house employs someone whose job is to ask where you got that. You do not have one. The check happens inside your own process or it does not happen at all, and the reader who finds the error is the one who tells everybody else, in a review that stays up for years.
This is not only a nonfiction problem. Memoir makes claims about dates, places and living people. Historical fiction makes hundreds in passing — what a character eats, wears, rides and says. A contemporary novel makes them too, about a city you visited once. If a sentence could be wrong in a way a stranger could demonstrate, it is a factual claim, and it is yours to stand behind.
What to check first
You are not going to verify every sentence. Work down this list, because the order reflects both how often each class of error occurs and how much it costs you.
- Numbers and dates. The most-caught errors and the most damaging. A wrong figure is provable in seconds, and it makes a reader wonder what else went unchecked. Distances, populations, ages, years, durations, percentages, counts. Recheck every one that arrived in the text from memory or from arithmetic you did in your head.
- Names and titles of real people and organizations. The spelling, and the title the person actually held at the time of the scene. Institutions rename themselves, merge and close; the name in your 1994 chapter may not be the name on the building today.
- Quotations and who said them. The two halves fail independently. The wording drifts with each retelling, and the attribution migrates toward whoever is more famous. A quotation you have seen a hundred times is more likely to be misattributed, not less.
- Anything you learned a long time ago and have not verified since. Fields move. The fact you have repeated confidently since a class twenty years ago is exactly the one that has been revised in the meantime.
- Anything you are certain about. Certainty is the strongest predictor of an uncorrected error, because certainty is what stops you looking. The claims that reach print wrong are almost never the ones you marked as shaky.
Keep a source note as you write
The habit that makes all of this manageable costs a few seconds per claim: when you write a fact, write down where it came from, right there.
A bracketed note in the draft, a comment, a line in a separate file keyed to the chapter — the form does not matter, and none of it reaches the reader. What matters is that it exists before you have forgotten.
Reconstructing sources afterward takes longer than collecting them did, and it is a worse job. You end up hunting for a page that agrees with a sentence you have already written, which is a different activity from finding out what is true. Keeping track of your research goes through the note systems that survive a long project. Keep them with your other production decisions; The style sheet: how a series stays consistent is the natural home for them.
One source repeated is not several sources
Prefer primary material: the record, the register, the paper, the transcript, the photograph, the person. A secondary source is someone else's fact-check, and you inherit their errors along with their facts. Where the person is the source — a memoir told to you, an oral history, a business book built on conversations — Writing a book from interviews covers recording, transcripts and what to agree before you start.
Three pages agreeing proves nothing on its own. A claim that traces back to a single unsourced article, quoted and requoted until it is everywhere, is not corroborated — it is echoed. Follow at least one chain back to where it starts. If the origin turns out not to exist, you have learned something more useful about the claim than any amount of agreement could tell you.
In the tools. Nothing here checks facts for you — a claim is yours. What the tools do is keep the production side honest: previews are free, unlimited and watermarked, so you can read real typeset pages during a fact pass instead of proofing a manuscript file. Start your book → · about the tools
Historical fiction: check the objects, not the plot
Readers of historical fiction forgive invention and punish anachronism. Nobody writes in to say your duke never existed. They write because a character in 1840 glanced at a wristwatch.
So check the furniture of the scene rather than the story. Objects, materials, food, transport, clothing, weapons, technology — and the part authors miss, the words. A term that entered the language in 1935, in the mouth of a Victorian, breaks the scene as thoroughly as the wrong rifle does, and slang dates faster than machinery. Look up first-use dates for any phrase that sounds modern to your own ear, then for a few that do not.
Dates and days of the week
Where your text names a date and a weekday together, check the pair against a perpetual calendar. It takes seconds and it catches a surprising number of errors, because timelines assembled over a long drafting period drift quietly.
The same check works on internal chronology. Count the travel days, the gestations, the school terms, the ages against the birth years. Arithmetic done across eighteen months of writing is arithmetic done badly.
When you cannot verify something
Sometimes the source is gone, contradicts itself, or sits behind a door you cannot open. You have three honest moves, and inventing confidence is not among them.
- Say so in the text. By most accounts, her family remembers it as, the records disagree. Attributed uncertainty is a normal feature of good nonfiction, not a weakness.
- Soften the claim to the part you can stand behind. Often that part is enough to carry the paragraph.
- Cut it. Usually the right answer, and always the fastest.
Corrections cost less than you think
A published error is fixable. An ebook can be corrected and re-uploaded; a print book carries the fix into the next printing. See Updating an ebook after it is published and Fixing a book that is already published for the mechanics of each.
A correction large enough to change what the book says, rather than repair it, stops being a correction and becomes a new edition, with its own edition statement and usually its own ISBN — see When a book becomes a second edition.
What is not cheap is defending an error. A correction made plainly, and acknowledged where readers will see it, costs a fraction of the credibility that an argued one does. Fix it, note it, and go back to work.
Make your book
The tools are free to use: name your book, bring your manuscript or your artwork, and work as long as you like. You only pay when you want the files without the preview watermark.
Next: Writing about real people · More: Proofreading your own work, and when to stop · Quoting other people's work in your book · Footnotes, endnotes and the reader's patience