Sources & Methodology

What counts as a source

For factual claims that may affect a money decision, we prefer the original publisher: a government agency, regulator, official dataset, or the organization responsible for the rule or program. We use a secondary article only when it adds useful analysis and clearly names its evidence. Wikipedia may help orient research, but it is not our default evidence for financial claims.

How worked examples are built

Sample budgets and savings plans are illustrations unless a page explicitly identifies documented personal figures. We show the main inputs, keep the arithmetic reproducible, and distinguish a possible outcome from a guaranteed result. Prices, taxes, benefits, rates, and household needs vary by place and date, so readers should replace our assumptions with their own numbers.

How calculators are checked

Each calculator uses a visible set of inputs and a consistent formula. Results are estimates, not individualized advice. We test boundary cases such as zero values, unusually large values, and missing inputs, then explain important assumptions beside the tool. Calculator values are stored on the visitor's device when the Save option is used.

Primary sources we use regularly

Update and correction rules

A page receives a new updated date only after a material change to its figures, assumptions, recommendation, or explanation. Formatting changes alone do not make an article new. If you find a factual or calculation error, send the page URL, disputed statement, and a supporting source through our contact page.

Editorial responsibility

Mohsin Shahzad is responsible for the final published version of each guide. Digital tools may assist with research organization, calculations, editing, and formatting, but they do not remove the publisher's responsibility to check the final work. Read the full editorial policy and financial disclaimer for more detail.