Schulrechner

The calculator you know from school.

Frustrated by the lack of free, open-source scientific calculators that feel like the ones I am used to, I decided to reverse-engineer my old calculator from school.

• input of complex equations,
• output as fractions as well as decimals,
• result storage and reuse,
• selection and editing of equations from input history,
• and support for implicit multiplication (like 5p instead of 5*p),
• this calculator produces math that looks like the math on your paper. That makes it much more suitable for higher-level math in school and university—especially if you've grown accustomed to this kind of interface from a young age and just forgot your calculator at home.
• A well-established open-source math.js library as the math engine—so you're not relying on some sketchy, hand-rolled math logic (just my sketchy hand-rolled input method 😛)
• A familiar, intuitive design
• 100% offline usability and fully open source
• Written entirely in HTML, JS, and CSS, which means it is inherently cross-platform, ...
• easy for other web developers to contribute and ...
• admittedly a bit heavy for a calculator. If you're interested in helping make a lighter version (Flutter, Kotlin, etc.), you're very welcome!