Significant figures in lab reports
Carry adequate precision through calculations and round the final reported result once under the rule required by the operation or course.
Count significant digits in context
Leading zeros are placeholders; zeros between non-zero digits are significant; trailing zeros require decimal notation or scientific notation to make the intended precision clear.
Operation rules differ
Multiplication and division commonly use the least significant-figures input. Addition and subtraction commonly use the least precise decimal place. These are reporting conventions, not uncertainty analysis.
Keep guard digits
Preserve extra digits in intermediate calculations and round the final reported result once. Repeated intermediate rounding can create a traceable discrepancy even when the formula is correct.
Let uncertainty govern when applicable
An estimated uncertainty often determines useful reporting precision. Apply the actual course or laboratory convention rather than a mechanical rule when it specifies another treatment.
Sources and boundaries
Solice develops LabCrux. The independent sources above do not sponsor or endorse the product. This page explains a review method; your experimental evidence, course instructions, and instructor remain authoritative.