TL;DR:
Trace a claim to where the number first came from before you pass it on.
Check the date, what was counted and what it was compared with.
If you cannot verify it, say so or do not share it.
A post goes around: a bar chart with the headline "Library visits TRIPLED in our town!" You like your library and want to share it. Before you do, spend ten minutes checking. The check is not hard, and it often changes what you would have said.
Slow down at the moment you want to share
Claims spread because they make us feel something. A good habit is to treat the urge to share as a cue to check. The goal is not to doubt everything but to be sure that what you pass on is true, current and fair to the facts.
The four-step check
Trace the source: Ask where the number came from. A post that claims numbers should link to where they came from. Search for the phrase and the numbers together, look for the original report or dataset, and open it.
Check the date: Find when the figures were collected and when the post was made. A correct number from years ago can mislead today.
Check the context: What exactly was counted? Compared with what, and over what period? Is the chart's axis starting from zero? Context can turn a true number into a false impression.
Cross-check: Find one independent source for the same fact, such as a local government page, a news report that cites the original, or another dataset.
Worked example: a statistic seen on social media
The post says library visits tripled. The numbers below are invented to show the process.
Trace: the chart's small print names the town's library report. You find the report. It lists visits for each year.
Read the table: 2020 had 10,000 visits and 2023 had 30,000. So the post is arithmetically right: 30,000 ÷ 10,000 = 3.
Check the date: the post compares 2020 with 2023. Was 2020 a normal year? The report notes the library was closed for part of 2020.
Add context: the report also shows 2019 at 40,000 visits. Compared with that year, 2023 is 30,000 ÷ 40,000 = 0.75 of the earlier level, which means 40,000 − 30,000 = 10,000 fewer visits, a drop of one quarter.
Conclusion: the post chose a closure year as its starting point. Visits did triple compared with 2020, but they have not yet returned to their 2019 level.
So the claim is true but incomplete. A fair post would say: "Visits are up from the 2020 closure year, but still below 2019." That is less exciting and more useful. Recompute the figures yourself: 3 × 10,000 = 30,000, and 0.75 × 40,000 = 30,000.
Questions that expose weak statistics
Compared with what? A change is always a change from something.
Over what time period, and why those dates?
Who was counted, and who was left out?
Is it a count or a rate? A bigger place has bigger counts.
Does the chart axis begin at zero, or does it exaggerate small gaps?
Is this the original source or a screenshot of a screenshot?
When you cannot verify it
Sometimes you cannot reach the source. Then you have three honest choices: do not share, share with a clear note such as "I could not find the original data", or ask the poster for the source. Resist the middle path of sharing with "apparently" in front. Readers remember the claim, not your hedge.
Also remember that a claim can be both unverified and true. Your job is not to declare it false, but to avoid vouching for it.
Keep a record of what you checked
Write down, in a line or two, the original source, its date and what you confirmed. If someone replies "where did you get that?" you can answer in seconds, and if the source later updates its figures you know which of your posts or documents to revisit.
This matters most at work. A number that goes into a slide or a report travels further than a post does, and it is much harder to take back. A thirty-second note beside the number is cheap insurance.
Mistakes to avoid
Trusting a chart because it looks professional.
Checking only whether the arithmetic works and not whether the comparison is fair.
Stopping at a second site that merely repeats the first.
Treating a correction posted later as less important than the original post.
Doing it faster
Keep a short list of places that hold original data in your area, such as your local government's website, so you can go straight to them. The methods of finding reliable sources online apply directly. If you want a hand reading a source on your screen, DuckyHelper can look at it and answer out loud when you press fn on a Mac; the verification is still yours to finish, and organizing research notes helps you keep track of what you checked.
Frequently asked questions
Is a fact checker's website enough?
It is a good starting point. Open the sources it cites and read the date, because a check done long ago may no longer match current data.
What if the numbers are right but the framing is unfair?
Say so. You can share a corrected version with the fuller context rather than the original post.
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