A beginner-friendly path from first formula to practical workflows.
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Learn Run-Calc in four tiny wins
If this is your first calculator that works like a notepad, follow the steps below in order. Each step builds confidence, and each screenshot block is ready for your real app captures.
Visual Walkthrough
Type and press Enter
Write a simple expression and press Enter to get an instant inline result.
Example: 2 + 2 * 4 = 10
Great first check: try "+ 5", then change precision from the status bar.
Use Ctrl/Cmd + Enter if you only want to add a new line without calculating.
Store values in variables
Name important numbers once, then reuse them in later lines.
Example: subtotal = 89.5
Use plain names like taxRate or monthlyRent for readability.
Arrays are useful for grouped values: @bills = [45, 72, 18].
Process lists with pipelines
Use | to build readable steps like filter, map, and sum.
Example: bills | filter(# > 20) | sum
Think of | as "then do this" for data.
Inside filter/map, # is the current item in the list.
Ask AI for help
Start with ? to ask a question (like "What is 20% of 150?") , use ?? for a detailed explanation. IMPORTANT: you need to setup AI key before using this feature.
Example: ? Convert 6.5 feet to centimeters and show formula
AI can insert calculation lines you can review and rerun.
If your AI settings fail testing, use Revert changes to go back to last saved.
Operations Reference
Type a formula in plain text, for example: 2 + 2 * 4.
Press Enter to calculate the current line. Run-Calc adds the result inline: 2 + 2 * 4 = 10.
Start a new line with +, -, *, or / to continue from the previous result quickly.
Save values with variables so you can reuse them: total = 120 or @prices = [19, 35, 42].
Use | pipelines to process lists step-by-step: @prices | filter(# > 20) | sum.
Inside filter/map/each, # means the current item.
Need help from AI? Start a line with ? and write your request.
AI can return a number, an explanation, or ready-to-run calc lines. Numeric results are saved as ai0, ai1, and so on.
Configure AI in Settings -> AI. Changes are saved only after Test and Save succeeds.
Use " to add notes at the end of a line: total = price * qty " monthly subtotal.
Pressing Enter on an empty or comment-only line simply moves to the next line (or creates one at the end).
If a line is invalid, it is marked in red with a gutter ! so it is easy to spot and fix.
If you edit a line that already has = result, Run-Calc removes the old result so you can recalculate cleanly.
When a variable changes, dependent lines are visually marked as out-of-date until recalculated.
Status messages are written in plain language with practical examples for faster troubleshooting.
Copying results
Hover over any evaluated line to reveal a copy icon (⧉) next to the result.
Click the icon to copy the result value to the clipboard. The status bar confirms the copy.
Only numeric results are copyable — error lines do not show the icon.