Long Addition Calculator

The Long Addition Calculator lets you add multiple numbers together just like you’d do on paper showing each digit stacked neatly and even the carry-overs between columns. If you’re trying to visualize how a sum is built digit by digit, this tool spells it all out for you in real time.

You can paste in as many numbers as you like, and the tool will pad them out and align everything by place value. It handles multi-digit numbers cleanly and gives you the option to see the full carry process across each column. It’s great for checking your work, learning place value, or just breaking down sums into easy steps.

As you type or change options, the output refreshes automatically and flashes blue so you know it updated. Everything runs instantly in your browser no reloads, no delays.

Options
Show carry steps
Trim empty lines

How to Use:

  1. Enter Input
    Paste or type numbers one per line. Only digits are used any commas or symbols are ignored.
  2. Toggle Your Options
    • Show carry steps: Reveals each carry-over above the sum
    • Trim empty lines: Ignores blank lines in the input
  3. View the Output
    • The tool aligns numbers from the right
    • Shows addition column by column
    • Displays carry steps if enabled
    • Flashes blue whenever the output updates
  4. Use the Buttons
    • Calculate: Manually trigger the update
    • Copy Output: Copy to clipboard

What Long Addition Calculator can do:

This tool is perfect for breaking down sums the way you’d solve them in school. It’s especially useful for teaching or learning how multi-digit addition works the carry process, digit alignment, and the total being built step by step. Whether you’re explaining it to a student, checking your homework, or just visualizing number logic, this tool shows everything clearly.

Example:

Input:

345
789
62

Output (with carry):

1 1 1
+ 3 4 5
+ 7 8 9
+ 0 6 2
= 1 1 9 6

Common Use Cases:

This is great for math teachers creating visual aids, students learning place value, or anyone who wants to break apart addition in a structured, easy-to-read way. It removes the guesswork and turns number crunching into something you can literally see stack up.

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