Last updated: 10/11/2026
Who makes it
Javier Mohino runs EchaCuentas and writes and reviews every calculator, its formulas and its text. With a degree in Mathematics applied to Data Analysis and four years specializing in data analysis and everyday money math, Javier Mohino created EchaCuentas to meet a need everyone has: the official figures that affect us and the news that explains them, in one place, instantly, with the math already done.
Mission
To let anyone run an important calculation and understand the result. Many tools return a number without saying where it comes from; here every calculator shows the formula, an example worked out by hand, answers to common questions and, when the result depends on a rule, a link to the official source.
What makes us different
- Transparency: no black boxes. We explain the method and, when a calculation depends on a law or a study, link the source, such as the IRS, the Department of Labor or the NIH.
- Privacy: calculations run on your device. No sign-up, and we do not store what you type.
- Speed: the result updates as you type, on your phone too.
- Useful extras: share a calculation with a link, save it to your history or download it to Excel.
How we work
Before publishing a calculator, we test it against several cases worked out by hand, including edge cases. If it depends on a rule (tax brackets, withholding tables, overtime law), we review it when the rule changes and at least once a year. The full process is in our methodology and our principles in the editorial policy.
How it is funded
EchaCuentas is free and funded by advertising. Ads are kept apart from the content and never affect the results or the text.
Get in touch
Missing a calculator, spotted an error or want to work with us? Write to us from the contact page. We read every message.