Where do our facts come from?
Serial formats come from primary sources only: the manufacturer’s website, its support or FAQ pages, and the installation, product data and service documents it publishes. We don’t take formats from contractor blogs, forums or other decoder sites, even when they’re probably right.
How are worked examples made?
Each worked example applies the manufacturer’s stated rule to a sample serial number. Unless a page says an example is quoted from the manufacturer, the serial is made up to show the rule and doesn’t belong to a real unit.
How are pages dated?
Each source on a page lists the date we last checked it. A page’s “Updated” date is the most recent of those check dates, and the same date is in the page’s structured data. A date only changes when someone re-reads the source.
What happens when we can’t confirm a format?
We leave it off the page and track it as an open item until we can confirm it with the manufacturer’s own source. A page with open items stays a draft and isn’t published.
How often are pages re-checked?
Every page is re-checked against its sources every quarter, and sooner when a manufacturer changes its serial format.
How do you report an error?
Email hello@whatyearis.com with questions or corrections. We correct confirmed errors and update the page’s check date.