Written Arithmetic Step Workbench

How to use Written Arithmetic Step Workbench

Choose addition, nonnegative subtraction, multiplication or integer division and enter two unsigned digit strings. The report follows the selected decimal algorithm one digit at a time and preserves carry/borrow inputs, written digits and checked result; all four operations share this one workflow.

1. Use the example as the schema; replace its labels and entered model assumptions.
2. Choose addition, nonnegative subtraction, multiplication or integer division and enter two unsigned digit strings. The report follows the selected decimal algorithm one digit at a time and preserves carry/borrow inputs, written digits and checked result; all four operations share this one workflow.
3. Calculate, inspect the complete witnesses and limitations, then copy or download the JSON report.

Good to know

• Each operand is 1–32 ASCII digits and may have leading zeros, which are normalized. No signs, decimals, separators or expression parsing. Subtraction requires left ≥ right; divisor must be positive. At most 1,056 multiplication digit steps plus 32 partial rows. This is an explanatory trace, not a copied textbook exercise or full handwritten diagram.
• Local calculation with no upload, input persistence or outside lookup. Model JSON is limited to 30,000 characters and 10,000 values. Decimal quantities are strings with up to six places; count fields use plain JSON integers. Exact fractions are capped at 8,192 bits. The complete JSON output is limited to 1,000,000 characters; approximate numbers preserve their stored values. Unsupported states fail explicitly.