Significant Figures Calculator

What is Sig Figs?

A sig-fig tool for science and engineering: it counts significant digits per the standard rules and rounds values to a requested precision.

How it works

Counting applies the rules (nonzero digits count, captive zeros count, leading zeros don't, trailing zeros count with a decimal). Rounding uses exponential-form digit targeting.

1. Enter your input. Type or paste your input into the field above — the tool responds instantly.
2. Review the result. Output updates live as you type. Everything runs entirely in your browser.
3. Copy or download. Use the Copy button to grab the result, or Download to save it as a file.

Examples

Realistic sample

Paste or type any realistic input — the tool computes the result locally and instantly.

Common mistakes

Expecting a server round-trip

Nothing is uploaded — every tool in this category runs entirely in your browser.