Formula
N = a × 10ⁿ, where 1 ≤ |a| < 10 and n is an integerEngineering: N = a × 10ⁿ, where n is a multiple of 3 and 1 ≤ |a| < 1000 How it works
Scientific notation writes a number as a value between 1 and 10 multiplied by a power of ten. It is the standard way to handle very large or very small quantities: the mass of the Earth is about 5.97 × 10²⁴ kg, and a red blood cell is about 8 × 10⁻⁶ m across.
To convert, slide the decimal point until exactly one non-zero digit sits in front of it. Count how many places you moved: moving left gives a positive exponent (big numbers), moving right gives a negative exponent (numbers smaller than 1).
Engineering notation is a variant where the exponent is always a multiple of three, so it lines up with metric prefixes — 10³ is kilo, 10⁻⁶ is micro, 10⁹ is giga. E notation (like 4.56e-5) is how calculators and programming languages print the same thing.
You can also go the other way: type something like 3.2e-4 or 3.2 × 10^-4 and read the plain decimal from the results. The digits are handled as text, so nothing is lost to rounding.
Frequently asked questions
What does a negative exponent mean?
It means the number is smaller than 1. 10⁻³ is 1/1000, so 4.5 × 10⁻³ = 0.0045.
Are trailing zeros kept?
In the scientific form shown here, trailing zeros are dropped. If those zeros are significant figures in your measurement, use the significant figures calculator to keep them, e.g. 4.5600 × 10⁻⁵.
How do I multiply numbers in scientific notation?
Multiply the front numbers and add the exponents: (2 × 10³) × (4 × 10⁵) = 8 × 10⁸. If the front number reaches 10 or more, shift it back and adjust the exponent.