About Dumb Bambi

Who operates Dumb Bambi

Dumb Bambi is an independently run website, published and maintained by its owner from the United Kingdom. It is not owned by a software vendor, a supplier or a hospitality group, and no third party pays for a calculator to produce a particular answer. If you need to reach the person behind the site, the fastest route is hello@dumbbambi.co.uk.

We deliberately do not publish invented author biographies, qualifications or "reviewed by" credits. Where a page names an author, that person genuinely wrote or checked it.

Why the site was created

Most of the day-to-day maths in a hospitality business is simple, and most of it is still done badly - on the back of a delivery note, in a spreadsheet nobody trusts, or not at all. The recurring errors are always the same handful: costing a dish against a VAT-inclusive menu price, confusing markup with margin, budgeting labour on gross wages and forgetting the on-costs, or judging a promotion on how busy it felt rather than the gross profit it produced.

Dumb Bambi exists to make those calculations fast, correct and free, and to show the working so the answer is understood rather than just copied. There are currently 20 calculators on the site, each with the formula, a worked example and the assumptions written out in plain English.

Who it is for

• Independent restaurant, café, pub and bar operators.
• Head chefs and kitchen managers costing dishes and writing specifications.
• Bar managers pricing a cocktail list and controlling wet GP.
• General managers writing rotas to a labour budget.
• Event and private hire teams pricing bookings.
• Small business owners and bookkeepers handling VAT, markup and margin.

How our formulas are researched, tested and reviewed

We only publish calculators for calculations with a settled definition, we state which definition we use, and we show the formula on the page. Every calculator is tested against an independently computed worked example - the same example published on the page - plus edge cases such as zero inputs and negative margins. Rates set by government are linked to GOV.UK rather than restated as our own figures, and we do not publish industry benchmark numbers we cannot evidence.

The full process, including our use of AI assistance and how translations are handled, is set out on our editorial and calculation methodology page.

How often we review changeable information

Every calculator page carries a "last reviewed" date. Pages that reference VAT, wages, National Insurance or pension rules are reviewed at least annually and again whenever a Budget or Autumn Statement changes a rate we mention. Arithmetic-only pages are reviewed annually. We update a reviewed date only when the page has genuinely been checked.

How to report a mistake

If a calculator gives a result you think is wrong, please tell us. Send the calculator name, the figures you entered and the answer you expected through our contact page or by email. Confirmed calculation errors are treated as a priority fix, and the page's reviewed date is updated when the correction goes live.

How the site is funded

The calculators are free, with no accounts, sign-ups or paywalls. The site is funded by advertising and by partnerships with hospitality suppliers. Advertising has no influence on any formula, worked example or recommendation, adverts are clearly labelled and kept away from calculator controls, and advertising cookies load only if you accept them in our cookie settings. If you would like to work with us, see partner with us.

Information, not professional advice

Everything here is general business information to help you understand your own numbers. It is not accounting, tax, legal or financial advice, and it cannot account for your specific circumstances or VAT position. Check any result against your own records, and take professional advice before decisions with real financial consequences. See our disclaimer for the detail.