Are my notes sent to a server?
No. Calculations run in your browser. Your draft is saved locally when storage is available; Clear removes it.
One expression per line. Define a value with name = expression; convert units with ->. Start a comment with #.
Result
Write one calculation per line and see results as you type. Name values to reuse them in later lines.
Use +, -, *, /, ^, %, parentheses and sum, avg, min, max, abs, round or sqrt. Convert compatible units with ->, such as 60 km / 2 h -> km/h. Length, mass, time, volume and derived units are supported.
Frequently asked questions
How do variables work?
Write budget = 1200, then use budget in later lines. Names use Latin letters, digits and underscores; start with a letter or underscore.
Which units can I use?
Length: m, km, cm, mm, in, ft, yd, mi. Mass: kg, g, lb, oz. Time: s, min, h, d. Volume: L, mL. Combine them with * , / and integer powers.
How do I add several values?
Use sum(a, b, c) for a total or avg(a, b, c) for an average. Values must have compatible units.
What happens when a line has an error?
The error appears beside that line. Later lines still calculate when their inputs are valid; an invalid variable is not reused as an old value.
Can I use this for financial calculations?
Results use ordinary floating-point arithmetic and display up to 12 significant digits. Check rounding for financial work; this is not an exact-decimal accounting tool.
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