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Calcadia

Data sources

Every rate on this site is copied from a document you can open yourself.

This page lists the publishers behind the calculators. Each calculator also carries its own Sources section naming the exact document its figures came from and the year those figures apply to, which is the list to trust if the two ever disagree.

Currency

Conversions use the euro reference rates the European Central Bank publishes on working days, read through the Frankfurter API.

Tax and salary, Canada

Federal and provincial brackets, along with payroll contribution rates and maximums, come from the Canada Revenue Agency.

Tax and salary, United States

Federal brackets and standard deductions come from the Internal Revenue Service. Social Security and Medicare figures come from the Social Security Administration.

Loans

Loan tools apply the standard amortisation formula to the figures you enter. There is no rate table behind them, so the only inputs are yours.

How sources are kept honest

Rates live in dated files in the code, one file per country per year, and every row stores the link it was copied from. A script walks those links and reports any that have moved or stopped responding, so a dead reference gets noticed rather than sitting there for a year.

When a new tax year takes effect, the previous year stays in place. Old results stay reproducible, and each page states which year it is showing. If you find a figure that no longer matches its source, tell me on the contact page.

Last updated .