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Independent worksheets
Calculators King publishes independent worksheets. There is no account, no saved history on a server, and no claim that a page is the official calculator of a school, a lender, a hospital, a game, or a government department. When a page uses a brand name that people already search, the page says it is not affiliated with that brand. The Banfield dosage page, the Blooket page, the Wordle page, and the NHS maternity page are examples. The arithmetic is ours. The trademark is not.
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Name the formula
The editorial rule is boring on purpose. Name the formula. Say whether a variance divides by n or by n minus 1. Say which quartile method is in use, which on these pages is the Hyndman-Fan type 7 position used by a great deal of statistical software. Say whether a proportion interval is Wilson or Wald. Say whether a geometric distribution counts the trial of the first success. A reader who disagrees with a convention can see it and can recompute. A reader who cannot see the convention is stuck trusting a black box.
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Similar tools stay separate
We separate tools that look similar because the decisions differ. The mean page will not quietly trim an outlier. The average page will, if you ask it to, and it will say that it did. The median page sorts and picks a position. The mode page tallies. Pooled variance and pooled standard deviation share inputs and return different headlines, because one is an input to a test and the other is a spread in the original unit. Line of best fit stops at the equation and the residuals. Linear regression adds a standard error, a t statistic, and an interval for the slope.
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Health and pay limits
Health, pay, and legal-adjacent numbers are treated as estimates. A due date from the last menstrual period plus 280 days is Naegele's rule, not a scan. An insulin dose on this site is carbs divided by a prescribed ratio, plus a correction from a prescribed factor, minus insulin on board. If you do not have those prescribed numbers, the honest output is that you should not invent them here. A WASPI illustration multiplies a weekly amount you type by the years between two pension ages you type. It does not announce an official compensation tariff, because there isn't one single public tariff this site can honestly apply.
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Numerical checks
Checks are numerical. The mean of 12, 7, 9, 15, and 10 is 10.6. A 95 percent two-sided z critical value is about 1.96. A t critical value with 10 degrees of freedom is about 2.228. Combinations of 10 things taken 3 at a time equal 120. Mortgage payments follow the standard annuity formula and can be compared with a known example. When a page fails one of those anchors, the page is wrong even if the prose sounds confident. The worked example loaded into each form is there so you can audit the same way.
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Who writes here
The people writing here are the Calculators King editors. We do not invent a founder biography, a fake clinic, or a street address we do not operate. Correspondence goes to hello@calculatorsking.com through the contact form or by direct email. Corrections are welcome, especially when a convention should be labelled more clearly or a statutory rate has moved. The NHS page, for example, defaults the weekly statutory rate to the published figure that applies from 6 April 2026 and leaves the field editable.
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Ads and density
Advertising may appear later if the site is accepted into an ad programme. The privacy policy explains what that would mean for cookies. Calculations themselves are not the product being sold back to you. The pages are dense on purpose: a short widget with two sentences underneath is not enough to teach a formula or to meet the standard we set for a reference page. Each calculator ends with five questions that a careful reader actually asks, and a blog sits beside the shelf when a topic needs a longer argument.
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Pick by the job
If you are choosing a first page, start with the job rather than the category name. A class average might be a mean, a trimmed average, or a median, depending on whether one score should be allowed to move the summary. A survey plan might be Slovin, Cochran, or Yamane. A home project might be concrete, decking, paint, or tile. The index is grouped so those choices sit together, and the search box will take a plain phrase such as standard deviation or pro rata.
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Edition dates
The reviewed date on calculator pages is 21-10-2026. Blog essays in this edition are dated 25-10-2026. Those dates are labels of the edition, not a claim that every public rate in the world froze. Where a rate is known to move, the field is editable and the steps name the date we used. If you are citing a page, cite the formula name and the inputs as well as the figure. A bare number without those three things cannot be checked by the next reader, which defeats the reason the steps are on the page at all.