Overview
Type or paste a measurement to see its significant-figure interpretation, scientific notation, and rounded outputs. The calculator understands 0.004560, 1200., and 1.200e3, keeps trailing zeros where appropriate, and highlights each decision in the steps log.
Switch to Round, Operations, or Batch mode to apply tie-breaking rules (half-up, half-even, away-from-zero), compare textbook versus final rounding, or process a whole list of numbers and expressions. Every action is reflected in the shareable URL so you can bookmark or send a working log.
Count reveals the sig-fig interpretation of a single number, Round controls significant or decimal rounding with tie rules, Operations evaluates + − × ÷ expressions with textbook vs final rounding, and Batch processes line-by-line inputs or CSV-style rows.
Result
How it’s calculated
FAQ
How does the calculator keep trailing zeros?
If a decimal point is present (0.004560 or 1200.), trailing zeros are treated as significant. Numbers in scientific notation always keep their full mantissa, so 1.200e3 reports four significant figures.
Which rounding rule should I choose?
Half-up mirrors common classroom rounding, half-even avoids bias in long sequences, and away-from-zero matches certain manufacturing or regulatory guides. Each option is applied consistently in textbook and final-only modes.