Reference library8 entries

Category: Precision

Core reference for precision, rounding, and significant figures, including the definitive sig fig calculator.

Error Propagation

Error Propagation: How Uncertainty Moves Through a Calculation

Learn the rules for propagating uncertainty through addition, subtraction, multiplication, division, and powers, with worked examples, common pitfalls, and standards citations from GUM, ISO,…

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Accuracy vs Precision

Accuracy, Precision, and Uncertainty: What Each One Actually Measures

Understand the distinct meanings of accuracy, precision, and uncertainty in measurement, with standards-based definitions, worked examples, and common pitfalls.

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Measurement Uncertainty

How to Read Uncertainty From a Ruler, Burette, or Digital Meter

Learn the correct way to interpret measurement uncertainty from analog and digital instruments, including significant figures, rounding, and standard conventions.

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Absolute vs Relative Error

Absolute Error vs Relative Error vs Percent Error: A Comprehensive Guide

Understand the differences between absolute, relative, and percent error, including formulas, when to use each, standards, and common pitfalls. A definitive reference for measurement…

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How to Calculate Percent Error (and Report It Correctly)

Learn the correct formula for percent error, how to handle significant figures and rounding, and avoid common pitfalls when reporting measurement accuracy.

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Error Propagation

Propagating Uncertainty Through Addition and Multiplication: Rules, Examples, and Standards

Learn how to propagate uncertainty when adding, subtracting, multiplying, and dividing measured values. Understand the significant figure rules, the GUM approach, and common pitfalls.

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Measurement Uncertainty

What Measurement Uncertainty Actually Is (and Why It Matters)

Measurement uncertainty is a quantitative expression of the doubt associated with a measured value. This guide explains its definition, evaluation per GUM, reporting conventions,…

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Measurement Uncertainty

How Many Sig Figs Should an Uncertainty Have? (Usually One or Two)

The uncertainty in a measurement should be reported with one or two significant figures, depending on the magnitude of the leading digit and the…

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