About Zopip

Zopip is a small independent project that builds free, fast calculators for everyday money questions: how much of my salary will I take home, what will my mortgage cost, how much does a loan really cost, how much will my savings grow.

How we build our calculators

• Official sources first. Tax brackets, social security rates and thresholds come from government publications (IRS, SSA, HMRC, Agencia Tributaria, Seguridad Social, Autoridade Tributária, Receita Federal, INSS, SAT). Every calculator lists its sources and the date it was last checked.
• Tested against worked examples. We check results against official tables and published examples before publishing and whenever rates change.
• Private by design. Calculations run entirely in your browser. We do not ask for your name, and the numbers you enter are never sent to us.
• Transparent about limits. Each page explains what is and is not included. Results are estimates, not professional advice.

Languages

The site is available in English, Spanish and Portuguese, with calculators for the United States, the United Kingdom, Spain, Portugal, Brazil and Mexico.

Contact

Found an error or want a new calculator? Email bunuzong@gmail.com.