Convert numbers to and from scientific notation.
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How do you convert a number to scientific notation?
Scientific notation expresses a value as a coefficient between 1 and 10 multiplied by a power of ten, for example 1.2345 × 10⁴. So 12,345 becomes 1.2345 × 10⁴ (1.2345e4), and 0.0042 becomes 4.2 × 10⁻³. This makes very large or very small numbers easier to read and compare, and the tool can also expand notation back to plain decimals.
Understanding your result
Scientific notation makes very large or very small numbers easier to read and compare.
Formula and method
Scientific notation expresses a value as a coefficient between 1 and 10 multiplied by a power of ten, for example 1.2345 × 10⁴.
Assumptions and limitations
It converts between plain decimals and scientific or E-notation and does not perform arithmetic between numbers written that way. The coefficient is normalised to sit between 1 and 10, and how many significant figures appear depends on the precision of the value you enter.
Worked example
12,345 becomes 1.2345 × 10⁴ (1.2345e4); 0.0042 becomes 4.2 × 10⁻³.
How to use this tool
- Enter a plain number or one in E-notation.
- Read the scientific, E-notation and decimal forms.
Common mistakes to avoid
- Writing a coefficient outside the 1–10 range.
About the Scientific Notation Converter
Convert a number into scientific notation and E-notation, or expand a number written in either form back to a plain decimal.
Who should use this tool
Science and engineering students handling very large or very small numbers, researchers reading measurements in E-notation, and anyone who needs to convert an unwieldy figure like 0.0042 into a compact power-of-ten form, or expand one back to plain decimal.
Benefits
- Converts both to and from scientific and E-notation
- Normalises the coefficient to sit between 1 and 10
- Makes very large and very small numbers easy to compare
- Expands notation back to a plain readable decimal
Practical use cases
- Writing a tiny measurement compactly for a lab report
- Reading a value given in E-notation from software output
- Comparing the magnitude of two very different numbers
- Expanding scientific notation into a plain decimal figure
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Frequently asked questions
What is E-notation?
It is the computer-friendly form: 1.2345e4 means 1.2345 × 10⁴.
What does the exponent's sign mean in scientific notation?
A positive exponent means the number is large, shifting the decimal point right, so 1.2345 times 10 to the 4 is 12345. A negative exponent means a small number, shifting the point left, so 4.2 times 10 to the minus 3 is 0.0042.
How do I convert scientific notation back to a normal number?
Take the coefficient and move the decimal point by the number of places given by the exponent, right for a positive exponent and left for a negative one. The tool does this expansion automatically when you enter a value in scientific or E-notation form.