A calculation you wrote three weeks ago is only useful if you can still tell what it was for. This guide covers both halves of that: annotating your math without breaking it, and getting the finished note out of the app.
Annotate Anything, Break Nothing
Besides // comments, there are three more ways to add a note to a line, and the math ignores all of them.
Labels. Start a line with a few words, a colon, and a space, and the label is ignored while the rest of the line still calculates:
| Note | Result |
|---|---|
| Rent: 1200 + 300 | 1,500 |
| Groceries: 85 + 40 + 22 | 147 |
Inline notes in parentheses. Drop a word in brackets anywhere in an expression and it disappears from the arithmetic:
| Note | Result |
|---|---|
| 100 (rent) + 200 (food) | 300 |
That is 300. Parentheses containing a real calculation still group as normal: 100 * (2 + 3) is 500, unchanged. The app decides based on what is inside the brackets, so you never have to think about it.
Quotes and hashes. Text in "quotes" is ignored the same way, and a line starting with # is a heading that never shows an answer. Together with //, that is four ways to write prose next to your numbers. The headings and comments reference covers headings and // comments in detail.
Labels also work in front of money and units, so Cost of iPhone: $999 and $5 (fee) // wire transfer both calculate correctly instead of going blank. The colon is optional too: words can sit right next to the numbers, so Rent 1200 + 300 shows 1,500 and $10 for lunch + 15% tip shows $11.50.
Your own text for a result. Hover over an answer and click the small ⋯ button (or long-press it on a phone) to copy the result, choose how many decimal places it shows, or replace it with your own text, like “Total”. Totals and line references still use the real value.
Conditionals Inside Expressions
A conditional does not need a line of its own: it can sit inside a larger expression.
| Note | Result |
|---|---|
| winter = false | false |
| gas = 120 | 120 |
| gas * (if winter then 1 else 0) | 0 |
There is a ternary shorthand too, winter ? 1 : 0 means the same thing, and and, or, not, and xor all work inside a condition:
| Note | Result |
|---|---|
| usage = 450 | 450 |
| winter = false | false |
| usage > 100 and usage < 900 ? 10 : 20 | 10 |
| not winter ? 1 : 0 | 1 |
Branches can hold more than plain numbers, so winter ? 10€ : 20€ returns money. The conditionals reference lists every supported form.
Expressions That Match How You Write Math
These expressions resolve the way you would expect on paper:
5 (2+3)is25, and2(3)is6: a number beside a bracket multiplies.-3^2is-9, not9, matching standard notation and your system calculator.-3!is-6.square root of 16andcube root of 27work as phrases, alongsidesqrt(16)andcbrt(27).- A typographic minus sign (
−), the kind you get pasting from other apps, subtracts instead of blanking the line. - An unfinished bracket or quote gives the best answer it can rather than nothing:
1 + (2is3.
Getting the Note Back Out
You can export a note as Markdown, plain text, CSV, or PDF, with the results included alongside the lines that produced them. Markdown keeps your headings, bold/italic, and lists intact. CSV is the one to reach for when a budget or an invoice needs to continue its life in a spreadsheet. See notepad calculator vs spreadsheet for where that handoff makes sense. PDF lays the note out as a two-column page with line numbers down the side, your note text, and the results next to each line.
Export lives in the tab’s context menu under an Export submenu, in the command palette, and on phones from the Notes list or by long-pressing a tab. Custom result text appears in every export format.
To send a note instead of a file, choose Share link from the same menus. The link opens the note in the web app, custom result text included.
Two Small Settings
Result alignment. Choose whether answers sit flush left, centered, or flush right in the result pane. Right alignment lines up the decimal points in a column of currency, which is the reason it exists.
Line rules. An optional faint rule under every line, ruled-notebook style. Off by default; turn it on if a long note is hard to track across.
The decimal separator defaults to your device locale rather than assuming a dot, so a comma-decimal region gets €1,50 without changing a setting first.
Try Notes Calculator free in your browser
Further Reading
The full syntax reference lives in the documentation. The pricing page covers the optional one-time upgrade: the calculator is free either way.