Scientific Notation Converter
Scientific notation writes very large or very small numbers compactly as a number between 1 and 10 times a power of ten. The speed of light, 299,792,458 m/s, becomes 2.99792458 × 10⁸. Enter a number in ordinary or e-notation to see all the common forms.
How to use the scientific notation converter
- Type a number, or use e-notation such as 6.022e23.
- Read scientific notation (one digit before the decimal point).
- Engineering notation is also shown, which uses exponents that are multiples of 3.
Formula
A number is written m × 10n with 1 ≤ |m| < 10 and n an integer. Move the decimal point until one non-zero digit is to its left; n is the number of places moved (positive if you moved left, negative if right).
Worked examples
Large number
123,456 → move the decimal 5 places left → 1.23456 × 10⁵.
Small number
0.00045 → move 4 places right → 4.5 × 10⁻⁴.
Working with scientific notation
Examples from science
| Quantity | Standard form | Scientific notation |
|---|---|---|
| Speed of light (m/s) | 299,792,458 | 2.99792458 × 10⁸ |
| Avogadro’s number | 602,200,000,000,000,000,000,000 | 6.022 × 10²³ |
| Diameter of a hydrogen atom (m) | 0.0000000001 | 1 × 10⁻¹⁰ |
| Earth’s mass (kg) | 5,972,000,000,000,000,000,000,000 | 5.972 × 10²⁴ |
Arithmetic rules
Multiply: multiply the coefficients and add the exponents. (2 × 10³) × (3 × 10⁴) = 6 × 10⁷.
Divide: divide the coefficients and subtract the exponents. (6 × 10⁷) ÷ (2 × 10³) = 3 × 10⁴.
Add or subtract: first give both numbers the same exponent, then combine the coefficients.
Significant figures
The digits in the coefficient are the significant figures. Writing 3.20 × 10⁵ signals three significant figures, while 3.2 × 10⁵ signals two. Scientific notation makes precision explicit, which plain numbers like 320,000 cannot.
Calculator entry
Most calculators use an EE or EXP key: type 3.2, then EXP, then 5 for 3.2 × 10⁵. In spreadsheets and code, write 3.2e5.
Practice problems
Try these yourself first, then check your answer. The answers come from the calculator above.
- Write 45,000,000 in scientific notation.
Show answer
Scientific notation: 4.5 × 10^7
- Write 0.0000072 in scientific notation.
Show answer
Scientific notation: 7.2 × 10^-6
Common mistakes to avoid
- Getting the sign of the exponent wrong. Big numbers have positive exponents and numbers below 1 have negative exponents.
- Leaving the coefficient outside 1–10, such as 12 × 10³, which is not proper scientific notation.
Frequently asked questions
What is E notation?
A calculator-friendly form where “e” means “times ten to the power”: 3.2e5 = 3.2 × 10⁵ = 320,000.
What is engineering notation?
Like scientific notation, but the exponent is a multiple of 3 so it lines up with prefixes such as kilo, mega and micro.
Why use scientific notation?
It makes huge and tiny values easy to write, compare and multiply, such as Avogadro’s number 6.022 × 10²³.
How do I multiply numbers in scientific notation?
Multiply the coefficients and add the exponents, then fix the coefficient if needed.
Reviewed September 26, 2026 by the SolveCalcPro editorial team. Found a mistake? Tell us; see our editorial policy.