Frequently asked questions

Each one is free and none requires an account. There is no gated result, no email wall and no paywall on any page. The full library, the formulas, the worked examples, the schedules and the sources are all open.

Yes. Save up to three scenarios on any calculator, change one or more inputs, and compare each saved result against the current one. A sensitivity table sits on every calculator page too, showing the headline result recomputed across a range of the input that drives it. Most publish a two-variable grid across two inputs at once.

Yes. Download a CSV with the inputs, the outputs and any schedule. Print the page as a formatted record. Or copy a share link that carries your entered values in the URL.

Each has an embed view at /embed/ followed by its slug, which renders the calculator without the surrounding page. Attribution back to the calculator page is expected, since the formula, limitations and sources live there.

Yes. Small screens are handled throughout: tables scroll horizontally inside their own containers instead of forcing the page sideways, and the full navigation is available from the menu.

Usually a convention difference: compounding frequency, whether a contribution falls at the start or end of a period, or a day-count basis. Each calculator prints its formula, so comparing the two formulas will normally show exactly where they diverge.

No. Calculations run in your browser. So the values you type are processed on your device and are not sent to a server. There is no account, no saved history and no profile. Closing the page discards them.

The numeric inputs you entered, placed in the URL so the recipient sees the same scenario. That means anyone with the link sees those numbers and any system the link passes through may retain them. Review a share link before sending it.

Account numbers, government identifiers, credentials or any other sensitive identifier. No calculation here requires them, and a share link would carry them into a URL.

The arithmetic follows the formula printed on each page and is verified two ways: an automated suite runs every calculator at worked-example, zero and extreme inputs, and core formulas are recomputed by a second method that reaches the answer differently: closed-form against simulation, bond price against explicitly discounted cash flows, tax against an independent bracket walk. Accuracy for your decision also depends on your inputs. It depends on whether real-world fees, rules or timing fall outside the model. That is why every page states its limitation boundary.

Whenever a balance, rate, term, tax rule, price, income or goal changes. For anything tied to current law or a product quote, verify against the dated official source or the actual disclosure immediately before acting , not relying on a figure computed earlier.

No. Results here are educational estimates, produced by a published formula from the values you enter. Nothing here is financial, investment, tax, legal, accounting or lending advice, an offer of credit, or a product quote, and no calculator ranks or recommends any product.

Primary sources: regulators, statistical agencies and the bodies that administer the programmes in question. Sources behind the definitions are listed on each calculator with links, and Free Calculators Online is independent of every organisation it cites.

A review date states when the calculation and its supporting text were last checked against their sources. It does not certify that no external rule has changed since. Nor is it a statement of suitability for any particular decision.

Send the page URL, the exact inputs you entered, the result shown, the result you expected, and the basis for expecting it. That is enough to reproduce the issue. We reproduce a report before changing anything, and a fix that alters a published figure moves that page's review date.

351, across 16 categories, alongside 29 guides and a glossary of defined terms. Calculators publish its formula, a worked example computed from prefilled inputs, a sensitivity table, definitions for every input, its limitations and its sources.

Search the full library. Browse by category. Or start from the answers pages, which list common money questions by topic with the formula and a link to the calculator that answers each one. Related calculators are linked from each page, that answer the next question.

Yes. Two machine-readable files are published. An index sits at /llms.txt. The full corpus is at /llms-full.txt, and it contains every calculator with its formula, inputs, computed result, sensitivity range, limitation boundary and sources, plus every guide and every defined term. Figures should be quoted together with the inputs that produced them and the qualifier that they are educational estimates.