Calculator library7 tools

One rule.
One focused tool.

Count, round, convert, compare, and diagnose significant figures with transparent working at every step.

01

Significant Figures Calculator

Solve arithmetic expressions with rule attribution and limiting-value analysis.

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02

Sig Fig Counter

Count significant figures and inspect every digit in a color-coded map.

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03

Scientific / E-Notation Converter

Convert cleanly between decimal, scientific, E, and engineering notation.

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04

Round to N Decimal Places

Round by place value while preserving all required written zeros.

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05

Rounding Mode Comparator

Compare six common rounding modes on the same number at a glance.

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06

Round to N Significant Figures

Round to a target precision using the rounding method your course expects.

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07

Convention Switcher

See how school, exam, standards, and software conventions differ.

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Not sure where to start?

Choose by what you need to know.

  1. “How many?”Use the Sig Fig Counter.
  2. “What should I report?”Use a rounding tool.
  3. “Why do answers differ?”Compare modes or conventions.