Significant Figures Calculator
Count significant figures and round a decimal value to a chosen precision.
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How to use this tool
- Enter a decimal or scientific-notation number, retaining meaningful trailing zeros.
- Choose a target precision from 1 to 30 and calculate.
Things to know
- Trailing zeros in an integer without a decimal point are treated as not significant. An explicit decimal point or scientific notation removes that ambiguity. Rounding uses half-up.
- One decimal of at most 120 characters; zero or magnitude 10^-100 to 10^100. Target precision: 1-30 significant figures. Extreme exponents are rejected before Decimal parsing.
- Use no more than 200,000 characters across the input and settings.
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