Scientific Notation Converter
Convert scientific notation
Convert scientific notation Runs locally in your browser
Enter a number.
About the
The Scientific Notation Converter expresses a number in the form mantissa times ten to a power, and shows the plain decimal form alongside it. It is the tool for reading values that arrive as 1.23e+8 or 4.5E-6, and for producing that form when a field, a spreadsheet or a spec wants it. Both directions come out of a single input, so you can check one against the other.
Where people use the
- Reading a value from a log, a config or a spec that uses e notation.
- Producing a compact form for a field that requires one.
- Checking the magnitude of a very small or very large figure.
- Converting measurements from an instrument into plain decimals.
How to use the
- 1
Enter a number
Either plain form such as 0.000045, or exponential form such as 4.5e-5.
- 2
Run it
The exponential form is shown with its mantissa and exponent, and the plain decimal form underneath.
- 3
Read the exponent
A positive exponent means a large number, a negative one a small number. The exponent is the number of places the decimal point moves.
- 4
Copy the form you need
Both are plain text, ready to paste.
Tips and best practices
- The exponent is simply how far the decimal point moves.
- Round the mantissa; six decimals is more precision than most sources justify.
- Very long integers lose precision; keep them as strings if exactness matters.
Frequently asked questions
What does e mean in a number?
It means times ten to the power of. So 1.5e3 is 1.5 times ten cubed, which is 1500. It is a compact way to write very large or very small values.
Why does the mantissa have so many digits?
Six figures are shown after the point, which is more precision than most sources provide. Round it to whatever your context needs.
Why does a long number lose digits?
Because the value is held as a standard floating point number with limited precision. Very long integers will not survive the conversion exactly.
Is the e notation the same as engineering notation?
No. Engineering notation forces the exponent to a multiple of three so it matches SI prefixes. This tool uses plain scientific notation.
Can I convert text that is not a number?
No. Anything that does not parse as a number is reported as invalid.