Long Addition Calculator
Calculate long addition instantly in your browser.
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What this tool does
Calculate long addition instantly in your browser. Whole numbers only; use the operation selector for long subtraction — a negative answer is shown when the second number is larger.
How to use the Long Addition Calculator
- Enter or select first number.
- Enter or select second number.
- Enter or select operation.
- Read the calculated result; change any measurement to compare alternatives.
Formula
Add or subtract column by column from the ones place, carrying (regrouping) 1 whenever a column reaches 10, or borrowing 1 from the next column when subtracting.
- a
- First number
- b
- Second number
- op
- Operation
Whole numbers only; use the operation selector for long subtraction — a negative answer is shown when the second number is larger.
Worked example
For long addition calculator, the following measurements illustrate the exact method: First number: 478; Second number: 259; Operation: add.
Inputs
- First number478
- Second number259
- OperationAdd
Result
- Sum737
Results explained
- Sum
- Sum from the formula above. Whole numbers only; use the operation selector for long subtraction — a negative answer is shown when the second number is larger.
Frequently asked questions
Add or subtract column by column from the ones place, carrying (regrouping) 1 whenever a column reaches 10, or borrowing 1 from the next column when subtracting.
Whole numbers only; use the operation selector for long subtraction — a negative answer is shown when the second number is larger.
Where mathematically meaningful, yes. Fields specify permitted ranges and undefined operations display an error.
Exact integer calculations use safe integers; decimal calculations use browser floating point, so small rounding differences can occur.
All values remain in your browser and are never uploaded.