About FactFile

FactFile records small, specific pieces of information that somebody looked up, verified, and wrote down so that the next person does not have to look them up again.

The unit is one claim. Not a subject, not an article — one sentence, with its source, the date it was checked, and where possible a screenshot proving it. A price, a fan count, a shipping policy, a compensation limit.

Verification states

Verified: Checked against its source on the date shown.
Potentially outdated: Was correct when checked, but is the kind of information that changes and has not been confirmed recently.
Needs review: Recorded but not yet confirmed against its source.
Disputed: Its accuracy has been questioned and it is being looked at.
Historical: Records what was true during a past period. Still correct about that period.
Archived: No longer maintained.

History is kept

When a fact changes, the previous version is not overwritten. A price that was £1,199 in May and £1,276.57 in September is two records, both correct about their own period. FactFile can answer what something costs now and what it cost then.

Corrections

Every fact page has a form at the bottom for reporting that something has changed or is wrong. Reports do not edit the record. They go to a queue, a person checks the source, and the fact is updated only if it needs to be.

Who wrote this

FactFile does not show who recorded a fact. There are no author pages, no usernames and no contribution counts. What matters about a claim is its source and its date, not who typed it in.

For machines

Every fact has a JSON and a Markdown form, and there is a search API and an MCP server. See the developer page or llms.txt.