Scientific Notation Converter

Write very large or very small numbers in scientific notation, E notation or engineering notation — or convert them back into an ordinary number.

How to use the Scientific Notation Converter

Type a number such as 123000, 0.00045, 6.02e23 or 3.2 × 10^5.
Optionally choose the number of significant figures.
Read the number in each notation.

How it works

Scientific notation writes a number as a × 10ⁿ, where 1 ≤ a < 10 and n is a whole number. Move the decimal point until one non-zero digit is left in front of it; the number of places moved is the exponent — positive for large numbers, negative for small ones. 123,000 = 1.23 × 10⁵ and 0.00045 = 4.5 × 10⁻⁴.

E notation (1.23e5) is the same thing written for calculators and code. Engineering notation uses exponents that are multiples of 3, matching SI prefixes like kilo, mega, milli and micro.

Powers of ten and SI prefixes

Power	Number	Prefix
10¹²	1,000,000,000,000	tera (T)
10⁹	1,000,000,000	giga (G)
10⁶	1,000,000	mega (M)
10³	1,000	kilo (k)
10⁰	1	—
10⁻³	0.001	milli (m)
10⁻⁶	0.000001	micro (µ)
10⁻⁹	0.000000001	nano (n)

Frequently asked questions

What is 5,000,000 in scientific notation?

5 × 10⁶.

What does 1e-3 mean?

1 × 10⁻³ = 0.001.

What is the difference between scientific and engineering notation?

Engineering notation always uses exponents divisible by 3 (10³, 10⁶, 10⁻³…), so 45,000 is 45 × 10³ rather than 4.5 × 10⁴.

How do I write 0.00072 in scientific notation?

7.2 × 10⁻⁴.

How do I multiply numbers in scientific notation?

Multiply the front numbers and add the exponents: (2 × 10³) × (3 × 10⁴) = 6 × 10⁷. If the front number reaches 10 or more, move the decimal point and add 1 to the exponent.