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Calculation Machine

Sig Fig Counter & Rounding Calculator

Count sig figs and round correctly.

Reviewed by the Calculation Machine team · How we check our maths

Your values

ⓘ Live results

Results
Significant figures
4
Rounded to 2 sig figs
0.0045
Scientific notation
4.520e-3
Decimal places
6
Ambiguous trailing zeros?
No

Working

  1. 10.004520 has 4 significant figures.

Quick answer

Significant figures are all certain digits plus one estimated digit; leading zeros never count, trailing zeros count only after a decimal point.

Worked example

Worked example

Using the values the calculator loads with.

Inputs

  • Number0.004520
  • Round to sig figs2

Result

  • Significant figures4
  • Rounded to 2 sig figs0.0045
  • Scientific notation4.520e-3
  • Decimal places6
  • Ambiguous trailing zeros?No

How to use the Sig Fig Counter & Rounding Calculator

  1. 1Type the number exactly as written, keeping trailing zeros.
  2. 2Set how many significant figures you need.
  3. 3Read the count and rounded value.

Frequently asked questions

Do leading zeros count?

No. In 0.00452 only 4, 5 and 2 are significant — the zeros just place the decimal point.

How do sig figs work in multiplication?

The result carries as many significant figures as the least precise input.

About this calculator