Notepad Calculator
Keep notes and math on the same page. Lines with an expression are evaluated, and the results are totaled.
🔒 Processed entirely in your browser — nothing you enter here is ever uploaded.
The result appears on this page after you run the tool. Nothing you enter is uploaded.
Result
About this tool
Type in the note box and run it. The page splits the text on line breaks and looks at each line alone. A blank line stays blank. A line is treated as math when it contains a number or closing parenthesis, then an operator, then another value, or when it starts with a function name and a parenthesis. A trailing expression after a colon or an equals sign is what gets parsed, so a line like hosting: 10 * 12 calculates 10 * 12. The original line is printed again with = and the formatted result. Lines that do not match, including ordinary sentences, are copied unchanged and do not enter the total.
The parser understands + − * / %, and ^ for power, with ^ binding tighter and associating to the right. Parentheses group. Names are abs, sqrt, sin, cos, tan, ln, log, round, floor, ceil, min, and max, plus the constants pi and e. Unknown names throw, and a throwing line is left as you typed it. The angle switch chooses degrees or radians for sin, cos, and tan only. In degrees, sin(90) is 1. Integers print as integers when they are within 1e21; other results use up to 14 significant digits.
Every successful value is added into one running total, negatives included. A note whose only line is 2+2 becomes 2+2 = 4 with Total: 4. The lines 2+2 and 3*4 become 4 and 12 with Total: 16. There are no stored variables: a name such as x is an unknown identifier, not a cell you assigned earlier. Copy and the calculated-note.txt download both contain the annotated note and the total. The text stays in the browser.
Example. A note whose only line is 2+2 is rewritten as 2+2 = 4, and the footer total is 4. In degrees, sin(90) equals 1 and adds 1 to that total.
Limit. A line with no arithmetic operator and no function call is copied through unchanged and does not add to the running total. A line that throws, such as an unknown name, is also left unchanged.
Can I mix notes and calculations?
Yes. Each line is inspected on its own. A line that contains an operator between values, or that starts with a function call, is evaluated and printed again with = and the result. A heading or a sentence with no operator is copied as written and stays out of the total.
Which functions and operators work?
Operators are + − * / % and ^, and ^ is right-associative. Names are abs, sqrt, sin, cos, tan, ln, log, round, floor, ceil, min, and max, plus the constants pi and e. The angle switch sends degrees or radians into sin, cos, and tan. sin(90) in degrees is 1.
How is the total added up?
Every successful result is added, including negative results. Two lines, 2+2 and 3*4, produce 4 and 12 and a total of 16. The copy button and the calculated-note.txt download both include the annotated lines and that total.