Scientific Notation Converter
Convert a number to scientific notation, a × 10ⁿ with 1 ≤ |a| < 10, and see its full decimal form. Type 6.022e23 to go the other way.
Last updated: October 2026
Scientific notation and decimal form
4.5 × 10⁻⁵ = 0.000045
Formula below · 2 sources (NIST, mathsisfun.com) · Updated Oct 2026
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About this calculator
Scientific notation writes a number as a × 10ⁿ, where the coefficient a has exactly one non-zero digit before the decimal point (1 ≤ |a| < 10) and n is a whole number. The exponent counts how many places the decimal point moves: a positive n for large numbers, a negative n for small ones.
0.000045 = 4.5 × 10⁻⁵ (the point moves 5 places right) 1,234,500 = 1.2345 × 10⁶ (the point moves 6 places left)
The calculator shows the normalized form and, when it fits, the full decimal after an equals sign. To go from scientific notation back to decimal, type the number in e-notation: 6.022e23 means 6.022 × 10²³, and 1.6e-19 means 1.6 × 10⁻¹⁹. Zero has no normalized form, because no power of 10 makes 0 a number between 1 and 10.
Engineering notation is a variant that only uses exponents divisible by 3 (45 × 10⁻⁶ instead of 4.5 × 10⁻⁵), so values line up with prefixes such as micro, milli and kilo.
| Power of ten | Decimal | SI prefix |
|---|---|---|
| 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) |
How to use
Type the number in the box. Leave out thousands separators. Example 1: 0.000045 gives 4.5 × 10⁻⁵ = 0.000045. Example 2: 1234500 gives 1.2345 × 10⁶ = 1,234,500. Example 3: −314 gives -3.14 × 10² = -314. Example 4: 1e22 gives 1 × 10²². Numbers this large are shown without the decimal form.
Frequently asked questions
How do you write a number in scientific notation?
Move the decimal point until one non-zero digit is left of it; that is the coefficient. Count the places you moved: moving left gives a positive exponent, moving right a negative one. 52,000 = 5.2 × 10⁴ and 0.0036 = 3.6 × 10⁻³.
How do I convert scientific notation back to a regular number?
Move the decimal point n places right for a positive exponent or n places left for a negative one, adding zeros as needed. 3.2 × 10⁵ = 320,000 and 7.1 × 10⁻⁴ = 0.00071. On this page, type 3.2e5 to see it.
What does 4e+5 on a calculator mean?
It is e-notation for 4 × 10⁵ = 400,000. The e stands for 'times ten to the power of', so 2.5e-3 is 2.5 × 10⁻³ = 0.0025.
How do I multiply or divide numbers in scientific notation?
Multiply (or divide) the coefficients and add (or subtract) the exponents, then renormalize. (3 × 10⁴) × (5 × 10³) = 15 × 10⁷ = 1.5 × 10⁸.
How do I add numbers in scientific notation?
Rewrite them with the same exponent first, then add the coefficients. 3.0 × 10⁴ + 5.0 × 10³ = 3.0 × 10⁴ + 0.5 × 10⁴ = 3.5 × 10⁴.
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