Scientific Notation Converter

Convert between ordinary numbers and scientific notation.

Order of magnitude
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Your result updates live as you type.

Scientific notation writes a number as a coefficient between one and ten multiplied by a power of ten. The speed of light becomes 2.998 × 10⁸ metres per second, which is easier to read, easier to compare and unambiguous about precision in a way that 299,800,000 is not.

Engineering notation is a close cousin that restricts the exponent to multiples of three, so it lines up directly with the metric prefixes: kilo, mega, giga, milli, micro, nano. That makes it the more practical form when the numbers describe physical quantities, and this page reports both alongside the matching prefix.

The scientific and engineering notation table follows the calculator: 6 rows spanning Speed of light (m/s) through One micron (m), there so the result can be cross-checked against a value you already trust. The page opens with number already set to 299,792,458, so there is a finished result on screen before anything is typed. The result is also read against 4 bands, from below one at the low end to astronomical scale at the high end, each with a note on what that range means in practice. The pages people most often open next are Number to Words Converter and Significant Figures Calculator.

The formula

x = a × 10n, where 1 ≤ |a| < 10
x
The original number
a
The coefficient, or mantissa
n
The exponent, or order of magnitude

How it works, step by step

  1. Enter your number in ordinary form.
  2. Choose how many significant figures to show.
  3. The gauge shows the order of magnitude.
  4. The scientific and engineering forms appear below.

Worked examples

The speed of light

299,792,458 m/s becomes 2.998 × 10⁸ at four significant figures. The exponent 8 is the order of magnitude, and engineering notation gives 299.8 × 10⁶, or 299.8 mega.

A very small number

The mass of an electron, 0.00000000000000000000000000000091093 kg, is 9.109 × 10⁻³¹ kg. Writing it out in full is impractical and hides the precision entirely.

Checking the Earth mass (kg) row

The reference table lists Earth mass (kg), giving Scientific: 5.972 × 10^24, Engineering: 5.972 × 10^24, Prefix: yotta. Entering that above should reproduce the same figures — if it does not, the input is being read differently to the way the table assumes.

How to read your score

—–0Below oneA fractional quantity, needing a negative exponent.
0–6Everyday scaleUnits through to millions.
6–12Large scaleMillions through to trillions.
12–—Astronomical scaleBeyond a trillion.

Frequently asked questions

What is the difference from engineering notation?

Engineering notation restricts the exponent to multiples of three so it aligns with metric prefixes. Scientific notation keeps the coefficient between one and ten.

How does this handle precision?

Scientific notation states precision unambiguously. Writing 1.20 × 10³ makes clear there are three significant figures, which 1,200 cannot express.

What is the order of magnitude used for?

Quick comparison. Two quantities differing by three orders of magnitude differ by a factor of a thousand, which is often all you need to know.

Are E notation and scientific notation the same?

E notation, as in 2.998E8, is the same value written for computers. It means exactly the same thing as 2.998 × 10⁸.

What do the bands under the order of magnitude mean?

They label the figure so it can be read without a reference point of your own: Below one up to 0; Everyday scale from 0 to 6; Large scale from 6 to 12; Astronomical scale from 12 upwards. The band is a reading aid only — the number itself is exact, and a value sitting just over a boundary is not meaningfully different from one just under it.

What formula does the Scientific Notation Converter use?

It computes x = a × 10^n, where 1 ≤ |a| < 10, where x is the original number; a is the coefficient, or mantissa; n is the exponent, or order of magnitude. The same expression is printed on the page above the inputs, so the result can be reproduced by hand or in a spreadsheet.

Numbers in standard form

Scientific and engineering notation
ValueScientificEngineeringPrefix
Speed of light (m/s)2.998 × 10^08299.8 × 10^6mega
Avogadro constant6.022 × 10^23602.2 × 10^21zetta
Electron mass (kg)9.109 × 10^-31910.9 × 10^-33outside range
Earth mass (kg)5.972 × 10^245.972 × 10^24yotta
Planck length (m)1.616 × 10^-3516.16 × 10^-36outside range
One micron (m)1 × 10^-061 × 10^-6micro

Engineering notation keeps the exponent a multiple of three to match metric prefixes.

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