Found a problem? Email [email protected]. We reproduce the issue, fix it at the source, re-run the calculator's automated test to confirm the fix, and update the page's review date. Reporting is free and never needs an account.
Calculator Matters is an independent project maintained by a single operator who is directly accountable for its accuracy. We work to keep every formula, example, and result correct, but we do not claim perfection — formulas can be implemented incorrectly, references can change, and edge cases can surface. Accuracy reports are treated as the highest priority, and confirmed errors are fixed as quickly as is reasonably possible.
How to report an error
Email [email protected] or use the contact page. Reporting an issue is always free and never requires an account.
What to include
To help us reproduce and fix an issue quickly, please include where you can:
- The calculator name or page URL.
- The exact inputs you entered (including currency and any options).
- The result you saw, and the result you expected.
- A reference or source for the expected result, if you have one.
- Your device and browser, if the problem looks like a display or input bug.
How we classify a report
We reproduce the issue with your inputs and then classify it, because different problems need different fixes:
- Formula error — the underlying math or implementation is wrong. Highest priority; it can change a published result.
- Input or unit error — a field is mishandled, mislabelled, or converts incorrectly.
- Display or rounding issue — the math is right but the presentation is misleading.
- Content error — a mistake in the surrounding explanation, example, or source.
- Working as intended — usually a difference in assumptions; we may then state the assumption more clearly rather than change the math.
How we review and re-verify a fix
We correct the formula, input handling, example, or wording at the source — not just the visible text. Before a corrected page is published, we re-run the calculator's automated test (which recomputes the result a second, independent way) and re-check the worked example against the corrected formula, so a fix cannot quietly introduce a different error. The full build-and-test process is described in our Methodology.
How we update a corrected page
- We fix the formula, input handling, example, or wording at the source and re-verify it as above.
- We update the page's review date when a correction changes a result, a formula, or a materially important explanation. Minor typo or styling fixes may not change the date.
- For a significant correction that changed a published result, we note what changed so returning users understand why a number may now differ.
Response times
We aim to acknowledge accuracy reports within a few business days and to resolve confirmed errors as quickly as is reasonable, prioritising anything that affects a published result. As an independently run site we cannot promise a guaranteed response time, but accuracy is treated as more important than any other work.
Rate and rule changes
Some results depend on figures that change over time, such as tax brackets, contribution limits, or stamp-duty rates. For those tools we label the relevant year or note that rates are illustrative, and we link to the official source for the current figure. If you let us know a published rate is out of date, we will review and update it.
Our accuracy commitment — and its limits
We aim for every calculator to be correct and clearly explained, and we act on confirmed errors promptly. We do not, however, guarantee that every result is free of error or current at all times, and results remain educational estimates rather than professional advice. For decisions that matter, verify the inputs and consult a qualified professional. See our full Disclaimer, our Editorial Policy, and our Methodology.
Corrections FAQ
How do I report an error?
Email [email protected] or use the contact page. Include the calculator name or URL, the exact inputs you entered, the result you saw, and the result you expected (with a source if you have one). Reporting is always free and never needs an account.
How quickly will you respond?
We aim to acknowledge accuracy reports within a few business days and to fix confirmed errors as quickly as is reasonable. As an independently run site we cannot promise a guaranteed response time, but accuracy reports are prioritised over everything else.
What happens after a correction?
We fix the issue at the source, re-run the calculator’s automated test and worked example to confirm the fix, update the page’s review date, and — when a published result changed — note what changed so returning users know why a number may now differ.
My result differs from another site or my lender — is that an error?
Not necessarily. Differences usually come from different assumptions (rate basis, fees, rounding, or local rules) rather than a mistake. We will still review it; if it is an assumptions difference we often make that assumption clearer rather than change the math.
A rate or tax figure looks out of date — will you update it?
Yes. Tools that depend on time-sensitive figures carry a review date and link to the official source for the current number. If you tell us a published rate is stale, we will review and update it.