How a natural-language calculator works

1. Plain math is calculated instantly

If you type an expression such as “(120 + 45) × 1.08” or “15% of 240”, Adding evaluates it directly in your browser with a dedicated math parser. It follows the standard order of operations, handles parentheses and negative numbers, and never sends the expression anywhere. Paste a list with one value per line and Adding totals it, shows the average, and lists anything it skipped.

2. Questions in words are matched to a calculator

For a question like “150 customers paying $99 a month — what’s my annual revenue?”, an AI model reads the sentence and identifies two things: which calculator fits (here, recurring revenue) and which numbers belong in which inputs. The AI never produces the final number. If something important is missing or ambiguous — a price with no billing period, or a date that could be read two ways — Adding asks a short clarifying question instead of guessing.

3. Deterministic code does the math

Once the inputs are known, a tested formula computes the result. Money is handled carefully to avoid rounding errors; bill splits distribute leftover cents so shares add up exactly; break-even units round up to whole units; and impossible cases, like a percentage change from zero, are explained rather than shown as a misleading number. Each answer includes the formula and the steps used.

4. You stay in control

Every input remains editable, so you can explore what-ifs, compare two scenarios side by side, or continue with follow-ups like “add 8% tax” or “split it four ways.” Browse the full list of calculators or read the guides to learn the formulas yourself.