About DailySmartTools
DailySmartTools is a small, independent site of free calculators, converters and everyday tools, with plain-English guides that explain the maths behind them.
Why it exists
Most online calculators give you a number and nothing else. That makes it hard to know whether the number is right, or whether you have entered the right thing. Here, every tool comes with the formula it uses, a worked example you can check by hand, and a list of the mistakes people commonly make.
What you will find
- 46 tools across calculators, converters, everyday tools and productivity.
- Step-by-step guides with worked examples and practice questions, each linked to the calculator that does the arithmetic.
- Explainers on the ideas behind the numbers, such as why averages mislead or what makes a password strong.
How we work
- Calculations are tested. The calculation code is covered by automated tests, including edge cases such as leap years, month ends and rounding.
- Examples are checked. The numbers in worked examples are computed and compared with the tools before a page is published.
- Your data stays with you. Calculators and text tools run in your browser. What you type is not uploaded. See the privacy policy.
- Mistakes get fixed. If you find one, tell us. Our editorial policy explains how corrections work.
How the site is funded
The site is free to use. It may be supported by advertising, which is explained on the advertising page. Ads never change a result, and we do not accept payment to feature a tool or rank it higher.
Who runs it
DailySmartTools is published by The Machine Selle, based in Finland. You can reach us through the contact page or at themachineseller@gmail.com.
The tools and guides are for general information. They are not financial, legal, tax or medical advice, and you should check anything important with a qualified professional.