Sig Figs Calculator

Free online significant figures calculator for students, teachers, and scientists. Solve expressions, count sig figs, apply rounding rules, and handle log/ln operations with precision.

Sig Figs Calculator

Free online significant figures calculator for students, teachers, and scientists. Solve expressions, count sig figs, apply rounding rules, and handle log/ln operations with precision.

110
3 significant figures

Results

Evaluated value
1.9276458134077032
Rounded to 3 sig figs
1.93
Addition/subtraction rule
n/a

Significant figures

  • 1.52 sig figs
  • 51 sig fig
  • 11 sig fig

Rules

  • Any non-zero digit is significant.
  • Zeros between non-zero digits are significant (e.g. 205, 3.604).
  • If there is a decimal point, trailing zeros are significant (e.g. 90.7500).
  • Leading zeros are not significant (e.g. 0.0025 has 2 sig figs).
  • Addition/subtraction round by least number of decimals.
  • Does not apply the even rule.

About the Significant Figures Calculator

Our Significant Figures Calculator is the most comprehensive and accurate tool for counting significant figures, solving mathematical expressions, and applying proper rounding rules for scientific calculations. Perfect for students, teachers, scientists, and engineers who need precise measurements and calculations in chemistry, physics, biology, and engineering applications.

This free online calculator supports complex mathematical expressions including addition, subtraction, multiplication, division, exponentiation, logarithms (log, ln), and scientific notation. The tool automatically applies significant figure rules and provides educational explanations to help users understand the underlying principles of measurement precision and uncertainty.

Key Features for Scientific Calculations

Advanced Expression Solver

Solve complex mathematical expressions with proper significant figure handling. Supports +, -, ×, ÷, ^, parentheses, log, ln, and scientific notation.

Accurate Sig Fig Counting

Automatically count significant figures following standard scientific rules. Handles leading zeros, trailing zeros, decimal points, and scientific notation correctly.

Addition/Subtraction Rule

Automatically applies the addition/subtraction rule, rounding results to the least number of decimal places among the operands for precise calculations.

Educational Features

Includes comprehensive rules, examples, and step-by-step explanations to help students and professionals understand significant figure principles.

Scientific Applications

Perfect for chemistry lab calculations, physics problem solving, engineering measurements, and any scientific work requiring measurement precision.

User-Friendly Interface

Responsive design with interactive number pad, preset expressions, real-time validation, and one-click copy functionality for easy use on any device.

Perfect for Students, Teachers & Scientists

Students

Master significant figures for homework, exams, and lab reports. Verify answers and understand the rules with step-by-step explanations.

Teachers

Create examples, verify student work, and demonstrate significant figure concepts with real-time calculations and educational content.

Scientists

Ensure measurement precision in research, lab work, and publications. Handle complex calculations with proper significant figure rules.

📖 How to Use the Significant Figures Calculator

Step 1: Enter Your Expression

Type your mathematical expression using standard notation. Supported operations: +, -, ×, ÷, ^, log, ln, parentheses, and scientific notation (e.g., 1.23e-4).

Step 2: Set Significant Figures

Use the slider to set your desired number of significant figures. The calculator will automatically round results to maintain precision.

Step 3: Get Results & Analysis

View the calculated result, significant figure count, and step-by-step explanation of how the rules were applied.

📐 Rules of Significant Figures - Complete Guide

Counting Significant Figures

Non-zero digits: Always significant (1, 2, 3, 4, 5, 6, 7, 8, 9)
Zeros between non-zero digits: Always significant (205, 3.604)
Trailing zeros with decimal: Always significant (90.7500, 1.200)
Leading zeros: Never significant (0.0025, 0.0001)
Trailing zeros without decimal: Not significant (100, 2500)

Calculation Rules

Addition/Subtraction: Round to least decimal places
Example: 12.34 + 1.2 + 0.567 = 14.1 (1 decimal place)
Multiplication/Division: Result has fewest sig figs
Example: 2.5 × 3.147 = 7.9 (2 sig figs)
Logarithms: Result has same decimal places as input
Example: log(123.4) = 2.091 (3 decimal places)

🔬 Advanced Features & Scientific Applications

Mathematical Functions

  • Logarithm (log): Base-10 logarithm with proper sig fig handling
  • Natural Log (ln): Natural logarithm (base-e) calculations
  • Exponentiation: Power operations with precision control
  • Scientific Notation: Full support for e-format numbers
  • Complex Expressions: Nested parentheses and operator precedence

Scientific Applications

  • Chemistry: Lab calculations, concentration, pH, stoichiometry
  • Physics: Measurement uncertainty, experimental data analysis
  • Engineering: Precision measurements, tolerance calculations
  • Biology: Statistical analysis, experimental results
  • Research: Publication preparation, data validation

💡 Practice Problems & Real-World Examples

Chemistry Example: pH Calculation

Problem: Calculate pH from [H⁺] = 2.5 × 10⁻⁴ M

Solution: pH = -log(2.5e-4) = 3.60 (2 sig figs from 2.5)

Physics Example: Density Calculation

Problem: Mass = 12.34 g, Volume = 5.6 cm³

Solution: Density = 12.34 ÷ 5.6 = 2.2 g/cm³ (2 sig figs from 5.6)

Engineering Example: Area Calculation

Problem: Length = 12.5 m, Width = 8.75 m

Solution: Area = 12.5 × 8.75 = 109 m² (3 sig figs from 12.5)

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Ready to Master Significant Figures?

Start using our professional significant figures calculator now. Perfect for students, teachers, scientists, and engineers!

Frequently Asked Questions About Significant Figures

How do you count significant figures?

Count all non-zero digits, zeros between non-zero digits, and trailing zeros when a decimal point is present. Leading zeros are not significant. For example: 0.0025 has 2 sig figs, 1.200 has 4 sig figs, and 100 has 1 sig fig.

What is the addition/subtraction rule for significant figures?

When adding or subtracting, round the result to the least number of decimal places among all operands. For example: 12.34 + 1.2 + 0.567 = 14.1 (rounded to 1 decimal place).

How do significant figures work in multiplication and division?

For multiplication and division, the result should have the same number of significant figures as the operand with the fewest significant figures. For example: 2.5 × 3.147 = 7.9 (2 sig figs, limited by 2.5).

Does this calculator support scientific notation?

Yes! Enter scientific notation using 'e' format (e.g., 1.23e-4 for 1.23×10⁻⁴). The calculator correctly counts significant figures in the coefficient and handles the exponent appropriately.

Is this calculator suitable for chemistry and physics?

Absolutely! This calculator is specifically designed for scientific applications including chemistry lab calculations, physics problem solving, engineering measurements, and any field requiring measurement precision and uncertainty analysis.

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