How to fact-check your own book
Extract every checkable claim into a list before you verify anything. Rank them by what happens if you are wrong. Verify the top of that list against primary sources, not secondary reporting. Keep a log with the source next to each claim. Then rewrite whatever you could not verify so it stops asserting.
The fact-checking pass, in order
Do it in this order. Verifying as you read is how a two-day job becomes a three-week one.
- Extract every checkable claim into one list before verifying anything.
- Add a column: what happens if this is wrong? Rank the list by that answer.
- Start with anything about a named living person. That is where the real risk is.
- Then health, money and legal claims. Then everything else.
- For each claim, find the primary source — the study, the record, the document.
- Never cite a news article's summary of a study. Find the study.
- Check every quotation against a primary source, especially famous ones.
- Check every number twice, and check what unit it is in.
- Verify spellings and current job titles of everyone you name.
- Build a chronology and check every date in the book against it.
- Log the source beside each claim. You will need it again in two years.
- For anything you cannot verify: cut, attribute, or say plainly that you cannot confirm it.
A separate free preview: A free outside view of your own pages
A separate editorial preview of one extract; it does not read the whole book or do the specialist job this page describes. Send up to 5,000 words. You get back what the draft appears to be doing to somebody who wasn't there when you wrote it, the strongest thing in it named, the exact place a reader starts to drift, and three revision priorities in order.
A separate editorial preview of one extract; it does not read the whole book or do the specialist job this page describes. An AI-assisted read of your own pages. Not a human edit, not a line edit, and not a scored report.
Separate extraction from verification
The single change that makes this manageable: build the whole list first, verify nothing while you read.
If you verify as you go, you will fall down a research hole on page four, spend an afternoon on a detail nobody will question, and lose the shape of the job. Extraction is a fast mechanical pass. Verification is slow and should be prioritised.
A spreadsheet with four columns is all you need: the claim, the page, the risk if wrong, and the source once you have it.
Rank by consequence, not by difficulty
Not all errors cost the same. Getting a bus route wrong is embarrassing. Getting a drug interaction wrong can hurt someone. Getting a statement about a named living person wrong can be actionable.
So rank the list by what happens if you are wrong, and work down from the top. Most authors do the opposite — they verify the easy ones first because it feels productive, and run out of energy before reaching anything that mattered.
Primary sources, and what counts as one
A primary source is the original record: the study itself, the census return, the company filing, the court judgment, the contemporaneous newspaper, the person who was there.
A secondary source is somebody's account of that record — and every layer adds drift. The classic failure is a statistic that appears in twenty articles, all citing each other, none citing the study, and the study says something meaningfully different.
For British authors the useful free primary sources are worth knowing: the ONS for statistics, the National Archives and county record offices for documents, Companies House for company facts, Hansard for anything said in Parliament, and the British Newspaper Archive for contemporaneous reporting. Most local libraries give free access to several of these.
What to do when you cannot verify something
You have three honest options, and only three.
Cut it. Usually the right answer for a decorative detail that is doing no work.
Attribute it. My mother always said, according to the parish record, the company's own account is that. This is not weakness; it tells the reader exactly how much weight to put on the claim.
Say you cannot confirm it. I have not been able to establish whether is a sentence that appears in serious non-fiction constantly, and it builds trust rather than costing it.
What you cannot do is leave an unverified claim standing as an assertion and hope. That is precisely the sentence a reader who knows the subject will write to you about.
About Your Book Pro
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Every account starts with 1,000 welcome credits, and a plain export of your own words is free.
Each guide says plainly when a person does the job better than AI. Guides on legal topics are general information, not legal advice.
Fact Check & Citations does the extraction pass — the slow, mechanical, easily-abandoned part. It reads the manuscript and returns the claim list: numbers, dates, quotations, named people and organisations, and causal statements, each located in your text, with the ones carrying no source flagged.
What you get is the spreadsheet described above, already filled in, which is usually where this job stalls when done by hand.
And the limit, stated clearly: extraction is not verification. The tool tells you what needs checking; it does not go to the archive for you. For books making health, financial or legal claims, a human fact-checker working against primary sources is a real purchase, and this makes their quote smaller because the extraction is already done.
If the book names living people in a way that could damage them, that is a different problem again — see the guide on writing about real people.
Check your claims
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Email me my free review linkQuestions people ask
- How long does fact-checking take?
- For a non-fiction book with moderate claim density, one to three weeks of your own working time. Books with heavy statistics take considerably longer, which is why professional fact-checking is priced by the hour.
- Should I include citations in the book?
- For academic and serious non-fiction, yes — endnotes rather than footnotes for general readers. For memoir and popular non-fiction, a short sources note at the back is usually enough and reads better.
- What about facts I remember but can't source?
- Attribute them to memory explicitly. 'As I remember it' is an honest and useful phrase, and readers trust a narrator who distinguishes memory from record.
- Do I need to check things in a novel?
- Check anything real: streets, dates, procedures, historical events. Readers with local or professional knowledge are your most engaged readers and the first to write to you.
- Is it worth hiring a fact-checker for a self-published book?
- If it makes health, financial or legal claims, or names living people, yes. For most memoir and general non-fiction, a disciplined pass of your own plus an extracted claim list gets you most of the way.