Scientific Notation Calculator
Convert numbers into standard scientific notation (a * 10^b) and engineering notation.
Mathematical Formula
Overview & Explanation
Scientific notation expresses very large or very small numbers in a compact normalized format: a coefficient times 10 raised to an integer exponent.
How It Works
- Move decimal point to create coefficient a between 1 and 10.
- Count number of places moved to determine exponent b.
Practical Applications
- Astronomy distances.
- Microscopic physics measurements.
Adding and subtracting in scientific notation
Multiplication is easy because you multiply the coefficients and add the exponents, but addition needs matching exponents first. To add 3.2 × 10⁴ and 5.1 × 10³, rewrite the second as 0.51 × 10⁴, then add the coefficients: 3.71 × 10⁴. For division, divide the coefficients and subtract exponents: (6.0 × 10⁸) ÷ (2.0 × 10³) = 3.0 × 10⁵. Normalise the result so the coefficient is at least 1 and below 10.
Significant figures and everyday examples
Scientific notation makes significant figures clear. Writing 4.50 × 10³ shows three significant figures, while 4.5 × 10³ shows two, even though both equal 4,500. When multiplying or dividing, keep as many significant figures as the least precise input.
It appears everywhere in science: the speed of light is about 3.00 × 10⁸ m/s, the mass of an electron is about 9.11 × 10⁻³¹ kg, and Avogadro's number is about 6.022 × 10²³. Calculators and spreadsheets often display it as E notation, so 6.022E23 means 6.022 × 10²³.
What scientific notation is
Scientific notation writes a number as a × 10ⁿ, where the coefficient a is at least 1 and less than 10, and n is an integer. Large numbers have positive exponents and small numbers negative ones. It makes very large and very small values readable and shows clearly how many significant figures a measurement has.
To convert, move the decimal point until one non-zero digit is left of it, and count the moves: moving left makes n positive, moving right makes it negative.
Worked examples
The speed of light, 299,792,458 m/s, is 2.998 × 10⁸ m/s to four significant figures. A bacterium 0.0000025 m long is 2.5 × 10⁻⁶ m. Multiplying (3 × 10⁴) × (4 × 10⁻²) gives 12 × 10² = 1.2 × 10³; you multiply coefficients and add exponents, then renormalise.
E notation
Calculators and spreadsheets often show scientific notation as 2.998E8 or 2.5e-6, where "E" means "times ten to the power". Engineering notation is a variant that keeps exponents in multiples of three (kilo, mega, micro), which matches SI prefixes.
Worked Example: 4,500,000 in Scientific Notation
Convert to scientific form.
Shift decimal 6 places left
4.5 * 10^6
Frequently Asked Questions
Why is scientific notation useful?
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