About CaloriesTools
CaloriesTools is a small collection of free calculators for people who want to understand their calories and nutrition. Each tool does one job, shows its working and explains what the result means.
What we believe
- You should not have to sign up for a number. There are no accounts, no paywalls and nothing to install.
- Your details are yours. Every calculation runs in your browser. Nothing you type is sent to us or stored on a server.
- A result without the working is hard to trust. Each result has a “Show the working” panel, and each page explains the formula and walks through an example.
- Every estimate has limits. We say where each number can go wrong, and we link to the research behind it.
Where the numbers come from
We use published, widely cited equations and do not invent our own. The adjustments we make, such as the calorie safety floor, are described on the page where they apply.
| Calculator | Method | Main source |
|---|---|---|
| Daily calories | Mifflin–St Jeor BMR, activity factor, then a goal adjustment of 250 or 500 calories | Mifflin et al., 1990 |
| BMR | Mifflin–St Jeor, with revised Harris–Benedict and Katch–McArdle for comparison | Mifflin 1990; Roza and Shizgal 1984 |
| TDEE | BMR multiplied by an activity factor from 1.2 to 1.9 | FAO/WHO/UNU 2004 |
| BMI | Weight divided by height squared, with WHO adult categories | WHO |
| Protein | Grams per kilogram for each goal | ISSN 2017; Morton 2018; PROT-AGE 2013 |
| Water | 35 ml per kg, plus allowances for exercise and heat. A rule of thumb, shown beside official intake figures | US National Academies 2005 |
| Calories burned | MET value × weight × hours | Compendium of Physical Activities, 2011 |
Who the calculators are for
They are written for healthy adults aged 18 and over. They are not designed for children, teenagers, or people who are pregnant, breastfeeding or managing a medical condition, and the results are not a diagnosis or treatment plan. Please read the disclaimer.
Independent and not medical
CaloriesTools is an independent project. We are not affiliated with the organisations whose research we cite. The content is general education and does not replace advice from a doctor or registered dietitian.
Corrections
If you think a calculation, a figure or a sentence is wrong, we want to know. Tell us which page it is on and what you entered, and we will check it against the original source, fix it if needed, and update the “Updated” date on that page.
Privacy
The short version is that we do not collect your calculator inputs. The full details are in the Privacy Policy.