Scientific Notation Converter

Scientific Notation Converter moves a number between its plain form and standard form, in both directions. Scientific notation writes a number as one digit, a decimal part, and a power of ten: the speed of light becomes 2.99792458 x 10^8 metres per second. It keeps very large and very small numbers readable and makes their order of magnitude obvious at a glance.

Engineering notation is the same idea with one restriction: the exponent must be a multiple of three. That lines it up with the SI prefixes, so 1.23 x 10^-4 becomes 123 x 10^-6 and can be read straight off as 123 micro-units. Datasheets, instruments and electronics calculators all use this form, which is why it is shown beside the scientific one.

Converting back is the other half of the job. Enter the mantissa and the exponent and the plain decimal comes out, which is the quickest way to sanity-check a figure copied out of a paper. Beyond about twenty places the plain form stops being useful and the result stays in exponent form, because a number with thirty zeros is harder to read, not easier.

The page shows its working, not just its answer. Where there is a formula it is printed with your own numbers substituted in, so you can check the result rather than take it on trust -- which is the difference between a calculator you can use for something that matters and one you cannot.

Everything runs inside your browser. What you type is never uploaded, never logged and never stored, and the calculator keeps working if your connection drops after the page has loaded.

• Shows scientific notation, plain number, engineering notation, exponent and si prefix together, so you are not running it twice
• A results table you can read across
• Prints the formula with your own figures substituted in
• Updates as you type, with no button to press and no page reload
• Copy the result in one click
• Free, no sign-up, and it runs entirely in your browser

The scientific notation converter is used by writers, developers, students, marketers and anyone else who needs the job done once without installing software. Common cases include:

• Writing a measurement in standard form for a report
• Converting a result into engineering notation and an SI prefix
• Expanding a figure like 6.022 x 10^23 into a plain number
• Checking the order of magnitude of a calculation