How to use the scientific notation calculator
- Type or paste a value into Number to convert. Plain numbers (299792458), commas (1,234,567), E-notation (6.022e23), powers of ten (1.6 × 10^-19 or 1.6x10^-19) and superscripts such as 3 × 10⁻⁴ all work.
- Leave Significant figures on Auto to keep your digits, or pick 1 to 15 to round.
- Press Copy beside the result you need. E-notation is the one to paste into code or a spreadsheet.
- For arithmetic, fill in First number (A), Operation and Second number (B).
How the conversion works
Scientific notation writes a number as a × 10n, with one non-zero digit before the decimal point in a and a whole-number exponent n. Move the decimal point until one digit is left of it. The places you moved are n: positive for a left move (large numbers) and negative for a right move (small ones). Engineering notation forces n to be a multiple of 3 so it matches SI prefixes such as kilo (10³), mega (10⁶) and pico (10⁻¹²), including the 2022 additions ronna (10²⁷), quetta (10³⁰), ronto (10⁻²⁷) and quecto (10⁻³⁰) listed by the BIPM. The calculator works on exact decimal digits, not floating-point numbers, so 0.1 + 0.2 is exactly 3 × 10⁻¹, and it rounds half-up only when you ask.
Worked example with the starting numbers
The page opens with 0.0000000000667, close to the gravitational constant. The decimal point moves 11 places right, so the tool shows 6.67 × 10⁻¹¹ and E-notation shows 6.67e-11. Engineering notation needs an exponent that is a multiple of 3, so it uses -12 with a coefficient of 66.7, shown as 66.7 × 10⁻¹², which the SI line reads as 66.7 pico (p). The written-out box returns 0.0000000000667. In the calculator, (3.2 × 10⁵) × (4.5 × 10³) gives 14.4 × 10⁸, renormalized to 1.44 × 10⁹, or 1,440,000,000.
Limits and edge cases
Trailing zeros count as significant only when the number has a decimal point: 1200 has 2 significant figures, 1200. has 4 and 1.200e3 has 4. Leading zeros never count. Exponents from -9999 to 9999 are accepted, far past the 10³⁰⁸ limit of ordinary calculators, but the written-out form is skipped past 10³⁰⁰. On Auto, a division that never ends, such as 1 ÷ 3, stops at 15 significant digits, and other results at 30. A comma must be a thousands separator, so 1,5 is rejected rather than read as 15. For percentages try the percentage calculator, and for very small chances the probability calculator.
Scientific notation FAQ
How do I convert a number to scientific notation?
Move the decimal point until one non-zero digit is left of it, then count the places you moved. The count is the exponent: positive for a left move, negative for a right move. So 0.0000000000667 becomes 6.67 × 10⁻¹¹ and 299,792,458 becomes 2.99792458 × 10⁸.
What is the difference between scientific and engineering notation?
Scientific notation keeps one digit before the decimal point and allows any exponent. Engineering notation keeps the exponent a multiple of 3 to match SI prefixes, so 6.67 × 10⁻¹¹ becomes 66.7 × 10⁻¹², or 66.7 pico.
Is scientific notation the same as standard form?
In the UK and several other countries, standard form means scientific notation. In the US, standard form usually means the ordinary written-out number, which is the Written out result on this page.
How do I multiply numbers in scientific notation?
Multiply the coefficients, add the exponents, then renormalize. For (3.2 × 10⁵) × (4.5 × 10³), 3.2 × 4.5 = 14.4 and 5 + 3 = 8, so the product is 14.4 × 10⁸, which is 1.44 × 10⁹.
Sources: BIPM, SI prefixes; NIST, Metric (SI) Prefixes; OpenStax Chemistry 2e, Measurement Uncertainty, Accuracy, and Precision.