Your First Calc

Build a simple tip calculator in 60 seconds.

What you’ll build

A tip calculator that splits the bill between friends. You’ll learn variables, percentages, and comments.

Step 1: Enter the bill

Type this in the first row:

bill = $86.50

The result shows 86.50. The $ tells instacalc this is a dollar amount.

Step 2: Add the tip

On the next row:

tip = bill * 20%

Instacalc understands 20% as 0.20. The result: $17.30.

Step 3: Split it

people = 4
per_person = (bill + tip) / people

Each person pays $25.95.

Step 4: Add a comment

Make it readable:

per_person = (bill + tip) / people  // each person pays

The // each person pays part becomes a comment. It shows next to the result so you remember what the row means.

What you learned

  • Variables: Name a number (bill = 86.50) and reuse it later
  • Percentages: Write 20% naturally — no need for * 0.20
  • Comments: Add // note to annotate any row
  • Dollar shorthand: Prefix with $ for currency formatting

Next steps